subaru justy l3-1.2 2wd carb repair

8/20/2019 Subaru Justy L3-1.2 2wd Carb Repair

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ributor: Service and Repairmoval and Replacement

Distributor

OVALRemove wires from distributor cap and remove cap.Disconnect primary wire.Remove distributor retaining bolt and remove distributor.Remove O-ring.

ALLATIONInstall O-ring onto distributor housing.Lube distributor housing LIGHTLY with anti-seize compound.Install distributor into cylinder and turn rotor to align.

NOTE: Distributor and cam are keyed. Distributor can only be inserted one way.

Install hold down screw and tighten slightly.Install distributor cap and wires.Connect electrical connector.Adjust timing.

ru Justy Hatchback 2WD L3-1.2L SOHC (Carb) 56


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ributor: Service and Repairassembly and Reassembly

Distributor

SSEMBLYRemove cap retaining screws, then the cap.

Fig. 63

Remove the screw securing the rotor and remove rotor.



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Fig. 64

Remove the rubber seal around the cap mating surface.Remove harness coupler from clamp.Remove screws that secure coupler clamp and remove clamp from housing.Remove the harness.WARNING Use needle nose pliers to remove the connector fron the pick-up coil, otherwise it may be damaged.

Fig. 66

Using two (2) standard screwdrivers, pry off the reluctor. Note which letter on the reluctor (top or bottom) for re-assembly.

Fig. 66

Remove the two (2) screws securing the breaker assembly to the housing and remove the breaker assembly.

Fig. 67

Remove the two (2) screws securing pick-up coil to breaker plate assembly and remove the pick-up coil.



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Fig. 70

MBLYAssemble in reverse order.Adjust reluctor air gap as follows:

a. Using a brass feeler gauge, measure the distance between the reluctor tips and each pole. b. Move reluctor until all gaps are equal.

AIR GAP CLEARANCE0.008 - 0.016 in (0.2 - 0.4 mm)



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ributor Cap: Description and Operation

Distributor Cap

POSEUsed to make the connection between the rotor and the correct spark plug wire.

ATIONOn top of the distributor.

RATIONHigh tension current from the rotor is distributed to the towers of the distributor cap at a pre-set sequence and then to the spark plug wireswhich carry the current on to the spark plugs.



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tion Cable: Testing and Inspection

Ignition Wires

g an ohmmeter, check ignition wire resistance. If resistance is not as specified, replace ignition wires as necessary.E OHMS

4590 - 107104580 - 106804110 - 95902900 - 6760



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tion Coil: Description and Operation

Ignition Coil

POSETransforms battery voltage into ignition voltage and delivers it in the form of a high voltage surge to the secondary ignition components.

ATIONOn firewall, near the brake master cylinder.

STRUCTIONThe ignition coil contains two sets of copper wire windings around a soft iron core. The primary winding is made of a hundred or so turns of

a heavy gage wire. It is connected to the battery through the ignition relay. The secondary winding contains several thousand turns of wirewound directly onto the iron core. The ratio of the number of wraps in the secondary winding to the number of wraps in the primarywindings determines the output voltage of the coil. The secondary winding is connected to the coil output tower through the iron core.

RATIONWhen current flow in the primary winding is stopped (by the ignitor), the collapse of the magnetic field causes a voltage to be induced in thesecondary windings. Voltage flows out of the coil's secondary terminal, through the ignition cable, into the spark plug and jumps theelectrode gap to ground causing a spark.



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tion Coil: Testing and Inspection

Ignition Coil Terminals

Disconnect coil connector.

Measure resistance of coil primary and secondary windings as follows:

PRIMARY

Terminal: Resistance:3 (+) & 4 (-) 0.81 - 0.99 Ohms

SECONDARY

Terminal: Resistance:3 (+) & secondary 8.5k - 11.0k Ohms



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tion Control Module: Description and Operation

Ignition Control System

POSEAllows the ECU to control ignition coil triggering operation.

ATIONOn the ignition coil bracket, near the master cylinder,

RATIONThe EFC System control unit determines the optimum ignition timing from the crank angle signal and other engine operating information and transmits an operating signal to the power transistor, resulting in spark plug firing. The control unit signal causes primary current to flow toground.

Actual spark timing is calculated from these factors:^ Advance angle when starting the engine.^ Advance angle at idle.^ Advance angle determined by engine speed and load under all driving conditions except starting and idling.A faulty power transistor does not set a trouble code.



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k-Up Coil: Adjustments

Fig. 70

Remove distributor.Loosen reluctor holddown screws.Adjust reluctor air gap as follows:

a. Using a brass feeler gauge, measure the distance between the reluctor tips and each pole. b. Move reluctor until all gaps are equal.

AIR GAP CLEARANCE0.008 - 0.016 in (0.2 - 0.4 mm)

Tighten screws.Re-install distributor, rotor and cap.Adjust ignition timing.



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rk Plug: Description and Operation

Spark Plug Cutaway View

POSESpark plugs allow high-voltage secondary current to arc across a small air gap to ignite the air/fuel mixture in the combustion chamber.

Spark Plug Temperature

T RANGEThe temperature of the spark plug is determined by the length of the insulator and the size of the heatsink area. The longer the insulator, thesmaller the heatsink area will be. This causes the spark plug to be hotter.

The heat range of the plug is determined by its ability to dissipate heat created during combustion. If too cold a plug is used, the possibility of fouling is increased. A plug that is too hot can cause preignition. Hotter plugs tend to burn cleaner with less deposit build-up. They can beused for stop-start city driving, but not for extended high speed or load conditions as engine damage can occur.



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rk Plug: Testing and InspectionOVAL

Twist and pull to remove ignition wire from plug.While wearing saftey glases, use compressed air to blow out debris from plug well.Using a 5/8" (16mm) socket, remove plug.

CAUTION : Use care not to allow foreign matter to enter through plug holes.

ECTIONCheck spark plugs for:Broken insulator

Worn electrodeCarbon depositsDamaged or broken gasketBurnt condition of porcelain insulator at spark gap.

NOTE : Dark deposits indicate too rich a fuel mixture. Light (white) deposits indicate too lean a fuel mixture, advanced ignition timing or insufficient plug tightening

Check plug gap and adjust to 0.039 - 0.043in (1.0 - 1.1mm).

ALLATIONAdjust electrode gap to 0.039 - 0.043 in (1.0 - 1.1 mm).Lightly coat threads of plug with anti-seize compound.

Install and thread plug into cylinder head by hand.Torque spark plug to 14 - 22 ftlb (20 - 29 Nm).Apply dielectric compound to the inside of ignition wire boot and install. A slight click will be heard when wire is properly connected.Tighten spark plug to specified torque. Overtorqueing may damage cylinder head threads.

RECOMMENDED SPARK PLUGS

BRAND PART NO.---------------------------------

NGK BPR6ES-11 NIPPONDENSO W20EPR-U11CHAMPION RC9YC-4



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rk Plug: Service and RepairOVAL

Twist and pull to remove ignition wire from plug.While wearing saftey glases, use compressed air to blow out debris from plug well.Using a 5/8" (16mm) socket, remove plug.

ALLATIONAdjust electrode gap to 0.039 - 0.043 in (1.0 - 1.1 mm).Lightly coat threads of plug with anti-seize compound.Install and thread plug into cylinder head by hand.Torque spark plug to 13 - 17 ft.lb (18 - 24 Nm).

Apply dielectric compound to the inside of ignition wire boot and install. A slight click will be heard when wire is properly connected.

OMMENDED SPARK PLUGSBRAND PART NO.---------------------------------

NGK BPR6ES-11 NIPPONDENSO W20EPR-U11CHAMPION RC9YC-4



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l Delivery and Air Induction: Description and OperationERAL DESCRIPTION

The fuel supply and air induction system is used to deliver the air/fuel misture to the combustion chamber.

The Fuel System consists of three major sub-systems:The fuel storage system,Feedback controlled carburetor, andThe fuel delivery and return system.

L STORAGEThe fuel storage system consists of a fuel tank, fill spout and filler cap.

DBACK CONTROLLED CARBURETORThe carburteor is a two-barrel down draft type. It consists of the following systems:1. Fuel resovoir system;

FloatReturn circuit

2. Primary circuit;Slow systemMain systemAccelerator pump systemChoke system

3. Secondary circuit;Step system

Main system4. Coasting fuel cut system5. Automatic choke system

For a more detailed description of the feedback control system operation, refer to Computers and Control Systems .

L DELIVERY AND RETURNThe fuel delivery system delivers fuel at a pressure and quantity high enough to maintain fuel in the carburetor under all driving conditions.

The fuel delivery components consist of fuel supply lines, a plunger-type fuel pump and a fuel filter assembly.

The fuel return system recovers excess fuel from the carburetor and returns it to the fuel tank. The fuel return line is low pressure and returnsdirectly to the fuel tank. The fuel return system consist of lines and couplings

L VAPOR RECOVERYThe fuel vapor recovery system provides a route for the recovery of fuel vapors (from the fuel tank and float chamber) either for storage inthe charcoal canister, or for evacuation through the purge control system. The vapor recovery system also consists of lines and couplings.Additionally contained in the vapor recovery system are two components, an overfill limiter and a fuel check valve. These componentsfunction as evaporative emissions control devices and are covered in detail in Emission Control Systems .



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l Delivery and Air Induction: Initial Inspection and Diagnostic Overview

All troubleshooting must begin by "Checking the Basics" . Certain basic faults can be undetectable by the self-diagnostic system of theECCS control unit and in some cases can actually interfere with the self-checking and fault memory operation. Low battery voltage, for example, can cause erroneous faults to set in control unit fault memories or can cause a system to go "Fail Safe" without setting a fault inmemory. On the other hand, system fault memories are cleared whenever the control unit or the battery is disconnected. Therefore, all faultmemories should be read prior to any vehicle power interruption or troubleshooting. Prior to any teardown, repair or component replacement,the following steps should always be considered.

PLAINT VERIFICATIONWhenever possible the repairing technician should personally verify the complaint. Having experienced the malfunction, the technician is

less likely to try to repair non-existent faults.

FUNCTION VERIFICATIONToday's sophisticated automotive systems are easily misunderstood, which can lead to repairs that attempt to force a particular system to

perform in a way that it was never intended to operate. Therefore, the troubleshooting technician should compare the system operation to thenominal system operation as described in the section Description and Operation . Furthermore, the technician is also encouraged to comparethe problem vehicle system operation with a known good vehicle.

VIOUS REPAIRSThe vehicle repair history can provide explanations to unusual complaints which seem to elude normal troubleshooting attempts. Incorrectcomponents or unapproved repairs can have subtle influences on seemingly unrelated systems.

TERY STATE OF CHARGE

Batteries in a state of partial discharge can have a dramatic effect of ECCS control units and related components.TIVE BATTERY CABLE INTEGRITYAll B+ connections must be in perfect condition for trouble-free electronic system operation. Refer to Diagrams for B+ interconnects.

BLE LINK INTEGRITYFusible links are employed to prevent possible damage to electrical components and wiring harnesses. These links and their connectionsmust be without dynamic resistance. Dynamic resistance can only be checked using the voltage drop method of testing.

ATIVE GROUND CONNECTIONSAs all electrical circuits are a circle, all B- connections must also be checked and verified to be in perfect condition. A poor "common"ground point will cause seemingly unrelated systems to influence one another. High current systems which encounter a poor "common"ground can back feed through other electrical systems causing unusual operation and perhaps inexplicable component failure. As with the B+side of the electrical system, the ground side should be checked dynamically using the voltage drop technique.

ER TRAIN CABLE ATTACHMENTSMetal cables attached to the engine or transmission which appear overheated and/or discolored indicate the need to thoroughly test all ground connections.

ER SUPPLY RELAYSFuel pump and main relays as well as their plug connections can be a source of intermittent operation which will not set a fault code in ECMmemory.

H TENSION COIL AND SECONDARY COMPONENTS WIRINGThe secondary ignition system should be checked visibly as well as with a suitable engine analyzer and scope. All components should beexamined for tight connections and freedom from carbon tracking, moisture and corrosion.

L DELIVERY AND FUEL RAIL PRESSUREFuel delivery must begin at once when cranking and the pressure in the fuel rails must be within specifications. Fuel pressure retention must

be maintained between the fuel pump outlet and the pressure regulator after engine shutdown.

RK PLUG CLEARANCEThe spark plug gap, if out of specification, can significantly impair engine performance. Spark plug type, condition and gap must verified according to specification.

UUM AND VAPOR HOSE INTEGRITYVacuum and vapor hoses must be routed correctly and not leaking. Always use the underhood label for primary information and refer toDiagrams for verification.

FUEL RATIOAdaptive engine management systems efficiently compensate for conditions which may affect the combustion process. However, whentroubleshooting idle quality or driveability complaints, it is still necessary to consider the following:^ Injector spray pattern quality^ Presence of unmetered air leaks^ Evaporative purge system



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^ Excessive engine oil dilution^ Substandard fuel or unapproved additives^ Carbon build-up

TING EQUIPMENTHigh standard testing equipment is essential if accurate results are expected. The use of faulty equipment will result in erroneous test results.Use only suitable test leads, terminals and probe tips.



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l Delivery and Air Induction: Symptom Related Diagnostic Procedures

gnostic Notes

This section is used to find the correct test procedure for a given symptom. The symptoms and actions in this section are Fuel related only.Refer to Fuel Injection and Computerized Engine Controls for complete Diagnosis By Symptom for Fuel, Ignition, Computerized EngineControls and Emissions. Verify the correct system application to ensure that the vehicle has the given component(s).

Before proceding to the appropriate symptom perform the following visual inspection:

NOTE: It is essential that the vehicle has been properly warmed up and is at operating temperature (except when attempting to diagnosis acold driveablity problem). The catalytic converter and feedback systems will not function as designed if this is not achieved. Failure to do sowill result in inaccurate test results.

Vacuum hoses for splits, kinks and proper routing.Ignition wires for cracking, hardness and proper connections at both the distributor and spark plugs.All wiring for proper connections, pinches, routing, and cuts.



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Troubleshooting



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l Delivery and Air Induction: Component Tests and General Diagnostics

ohol-In-Fuel Test

A fuel sample should be drawn from the bottom of the fuel tank so that any water present in the tank will be detected. The sample should be bright and clear.If the sample appears cloudy, or contaminated with water (as indicated by a layer at the bottom of the sample), this procedure should not beused, and the fuel system should be cleaned.

Using a 100 ml cylinder with 1 ml graduation marks, fill to the 90 ml mark.

Add 10 ml of water to bring the total fluid volume to 100 ml and install a stopper.Shake vigorously for 10 to 15 seconds.Carefully loosen the stopper to release pressure.Close the stopper and shake vigorously again for 10 to 15 seconds.Put the graduated cylinder on a level surface for approximately 5 minutes to allow adequate liquid separation.

If alcohol is present in the fuel, the volume of the lower layer (which would now contain both alcohol and water) will be greater than 10 ml.For example, if the volume of the lower layer is increased to 15 ml, it will indicate at least 5 percent alcohol in the fuel. The actual amount of alcohol may be somewhat greater because this procedure does not extract all of the alcohol from the fuel.

dback Carburetor System

eedback carburetor system will set trouble code 16 under the following circumstances:

f an improper tachometer can set code 16. If trouble code 16 is displayed in "D-Check" mode, conduct the check again using a differentmeter. If code 16 is now absent, the tachometer was the problem and the feedback system is okay.

de 16 is still displayed when using a proper tachometer, check if code 32 (oxygen sensor) is also displayed. If not, the mixture is too lean or ch and the problem is something other than the feedback system. If code 32 is present, troubleshoot the oxygen sensor system and repair assary.



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Speed: AdjustmentsUPDATED BY TSB# 027089 DATAED AUGUST 1989ANDTSB# 027289 DATED OCTOBER 1989

he following information to properly adjust the idle speed for engine and alternator electrical load when the air conditioner, blower fan or ights are engaged.

Remove the air cleaner assembly.

NOTE: Make sure the vacuum line from the intake manifold to the air cleaner in blocked off.

Figure 1

Temporarily connect the single pin black "Read Memory" connector (752) and the two pin green "Test Mode" connector (F51) located under the driver's side of the dash board. See Figure 1.Start the engine. Ensure proper operating temperature by waiting until the carburetor choke plate is fully open (or when the engine is notrunning in the fast idle warm-up mode.) Do not attempt to adjust cold.



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Figure 2

Using the chart and diagram in Figure 2, identify the type of transmission either manual or ECVT and perform the specified adjustments inthe sequence given. See Figure 2.



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Figure 3

Fig. 3

NOTE: For manual transmissions, step number 2, see explanation 5, Figure 3.

al Transmissions OnlyUse this procedure for condition number 2 (A/C on, blower fan on, and radiator fan on, if equipped). Locate the vacuum hose which connectsthe solenoid on the firewall to the top of the adjustable orifice. Temporarily disconnect the vacuum hose at the adjustable orifice and block itoff. Also, the adjustable orifice must be capped. See Figure 3.

NOTE: This adjustment in step 2 can only be performed while the compressor is running because when the compressor cycles off, the lever controlled by the actuator will move away from the adjusting screw.



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Figure 1

Verify the idle speed adjustments are correct. Turn the ignition off and disconnect the "Read Memory" and "Test Mode" connectors.

Reinstall the air cleaner and all hoses.

Start the engine and make sure the engine idles properly under all electrical and engine load conditions specified in the chart in Figure 2.

NOTE: The idle speed with the read memory end test mode connectors disconnected will be slightly higher in rpm. This condition is normal because the EFC system is controlling the idle speed.



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Fuel Mixture: Adjustments

Duty Cycle Graph

Idle Mixture Adjustment

Perform idle mixture adjustment only after carburetor was removed from engine or if carburetor required disassembly. Perform adjustment onboth main and slow duty solenoid valves using a suitable dwell meter. Set dwell meter range to four cycle (four cylinder) and adjust idleadjusting screw so that needle indicates a deflection equal to the following formula: Dwell(degrees) = 90/100 X Duty(%).

Connect a suitable tachometer and dwell meter.Warm up engine to normal operating temperature.Check dwell meter needle swing. If idle speed is satisfactory and duty ratio is as specified in the duty cycle graph (controlled, dwell meter needle steady), idle mixture is satisfactory.If dwell meter needle does not fluctuate normally (erratic), increase and maintain engine speed to between 2000 and 3000 rpm for approximately 2-3 minutes, then return to idle speed. If dwell meter needle swing is normal (controlled duty ratio), check idle speed and mixture (duty ratio). If idle speed and mixture (duty ratio) are incorrect, check the following components:

a. Ensure ignition timing is adjusted to specifications. b. Check for carburetor contamination.

c. Check vacuum hoses for condition and proper connection.d. Check condition of spark plugs.e. Check air filter element for obstruction.

Repair components as necessary, then check idle speed and duty ratio.Check dwell meter swing. If dwell meter needle continues to fluctuate erratically, refer to Computers and Control Systems section for further troubleshooting procedures.



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If dwell meter swing is normal, adjust duty ratio and idle speed to specifications by removing concealment plug using a suitable drill, thenrotating adjustment screw. If adjustment for duty ratio and idle speed cannot be obtained, refer to Computers and Control Systems sectionfor further troubleshooting procedures.If dwell meter swing is normal and duty ratio and idle speed are satisfactory, road test vehicle for approximately 10 minutes, then recheck adjustments. If duty ratio and idle speed are as specified, idle mixture is satisfactory.



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elerator Pedal Switch: Adjustments

Fig. 12 Accelerator & Throttle-position Switch Adjustment

Fig. 13 Accelerator & Throttle-position Switch Fault Chart

fer to Fig. 12, when checking accelerator switch or throttle-position switch adjustment.e accelerator switch should turn on .12-.28 inch from the accelerator pedal released position. The throttle position switch should turn on4 inch from the accelerator pedal released position. If either switch functions beyond specified ranges refer to chart, Fig. 13.



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elerator Pedal Switch: Locations

Instrument Panel Electrical Components

dal Bracket



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Filter Element: Description and Operation

Fig. 9 Air Cleaner

ir cleaner is mounted on top of the carburetor. It houses a round, pleated paper filter. It filters all air entering the engine.



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tude Compensator: Locations

Component Locations

the firewall.



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tude Compensator: Description and Operationh Altitude Compensator Solenoid Valve (Fed. Only)

HAC System

POSELeans fuel mixture when vehicle operates above approximately 3000 ft.



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Component Locations

ATIONAir passage is integral part of carburetor. Solenoid is on R.H. side of firewal.

RATIONWhen the vacuum/pressure sensor detects atmospheric pressure of 670 mmHg (26.38 in.Hg) or less, the EFC System control unit opens thehigh altitude compensator (HAC) solenoid valve to correct for the richer air/fuel ratio at high altitudes. The HAC valve then permitsadditional air into the carburetor auxiliary air passage near the main metering passage to lean out the mixture.



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tude Compensator: Description and Operationh Altitude Compensation System (HAC)

High Altitude Compensation System

POSELeans A/F ratio when the vehicle is driven at high altitudes.



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Engine Compartment Electrical Components

ATIONSolenoid is on firewall. Internal passages within carburetor.

RATIONThe control unit calculates the altitude from the signal sent via the vacuum/pressure sensor. When the vehicle is driven in high altitude, thecontrol unit energizes a control solenoid. The control solenoid then opens a passage, allowing air into the main air bleed of the carburetor,therby leaning out the mixture.



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tude Compensator: Testing and Inspection

High Altitude Compensation Schematic

A faulty high altitude compensator solenoid will set code 53 in the on-board diagnostic system. Refer to the schematic diagram and test thesolenoid with the diagnostic chart.

color code identification:

L: BlueB: Black Y: Yellow

G: GreenR: Red W: WhiteBr: BrownLg:Light greenGr: Gray

High Altitude Compensation Diagnostic Chart

H ALTITUDE COMPENSATOR DIAGNOSTIC CHART



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buretor: Description and Operation

eral Description

Fig. 7 Carburetor (Exploded View)

POSEProvides control for A/F mixture and engine speed.

ATIONOn top of intake manifold.

RATIONFuel mixture is drawn into the engine for combustion through the carburetor, using the venturi effect. As air is drawn into the engine by the

action of the pistons moving up and down in the cylinders, the narrowed carburetor throat (venturi) causes the air speed to increase and pressure to drop in this area. Fuel is then drawn from the float bowl through the main jets and main nozzle into the air stream. The amount of air flow and fuel spray is determined by the opening of the throttle valve and the pressure drop within the venturi area. The air and fuel isscattered (atomized) by the high speed air flow and vaporized before entering the intake manifold and being burned in the combustion

process.



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STRUCTIONThe carburteor is a feedback controlled, two-barrel down draft type. It consists of the following systems:Fuel resovoir system^ Float^ Return circuitPrimary circuit^ Slow system^ Main system^ Accelerator pump system^ Choke systemSecondary circuit^ Step system^ Main systemCoasting fuel cut systemAutomatic choke system

omatic Choke

Fig. 5 Automatic Choke

POSECompensated engine idle speed and A/F mixture for cold engine operation.

ATIONIntegrated into the carburetor top (choke chamber).

RATIONThe choke valve is linked to a bimetal spring through a choke lever, so the choke valve is kept open at an angle suitable for ambienttemperature by means of the bimetal spring force.

When the engine starts, the main vacuum diaphragm is operated by vacuum sensed at the downstream portion of the throttle valve. The chokevalve is opened by the vacuum piston and a connecting rod, preventing over-choking.

The auxilary vacuum diaphragm is also operated by vacuum to ease the setting angle of the bimetal spring through a linkage. This holds thechoke valve open slightly to prevent an over-rich mixture.

After the engine starts, a positive temperature coeffecient (PTC) heater warms the bi-metal spring and the choke gradually opens.

sting Fuel Cut (CFC) SystemPOSE

Improves fuel economy by closing the slow speed circuit (uses anti-diesel solenoid) in the carburetor during coasting.

ATION



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On right side of carburetor body.

RATIONThe coasting fuel cut (CFC) system activates the carburetor anti-dieseling switch during deceleration, closing the slow system fuel passage.The EFC System control unit detects deceleration when the following conditions are met:^ Intake manifold vacuum is below 590 mmHg (23.23 in.Hg) when the A/C is "OFF" and below 490 mmHg (19.29 in.Hg) when the A/C is

"ON."^ Vehicle speed is at least 40 km/h (25 mph).^ Engine speed is at least 1800 rpm.

When the control unit determines that the vehicle is decelerating, current to the anti-dieseling switch is interrupted, stopping fuel flowthrough the slow system passage. When coolant temperature is below 80° C (176° F), the control unit will not signal the system to stop fuelflow.

y Solenoid Valve

Duty Solenoid Valve

POSEControls A/F mixture in both the slow (idle) and main (cruise) circuits of the carburetor.

ATIONIn the carburetor body.

RATIONThe duty solenoid valve is controlled by a signal from the EFC control unit. The signal controls the duration ratio of current flow (dutyvalue). The valve is equipped with a control air bleed and a control fuel jet. When current is sent to the valve, a plunger inside movesdownward, opening the port to the control air bleed and closing the port to the control fuel jet. With no current, a spring moves the plunger upward to close the port to the control air bleed and open the port to the control fuel jet. These ports are routed to both the slow and main

ports on the primary side of the carburetor. The air/fuel ratio varies with the duration of current flow (duty value) through the duty solenoid valve.

at Chamber Ventilation (Fcv) SolenoidPOSE

Opens and closes a passage between the carburetor float chamber and the canister.



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Engine Compartment Electrical Components

ATIONOn the firewall.

RATIONWhen the ignition is at ON or START, the solenoid is energized and closes the vacuum hose connecting the float chamber and the canister.When the key is OFF, the solenoid opens the passage between the float chamber and the canister. This prevents fuel vapor discharge into theatmosphere. Refer to Emission Control Systems for further information.

at System



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Fig. 1 Float System

POSEMaintains a fuel resovoir in the carburetor.

ATIONAn integral part of the carburetor.

RATIONThe primary and secondary circuits of the carburetor share the same float system. Fuel flows from the fuel pump through the lines to the inletof the carburetor where it passes through the needle and seat. Fuel entering the chamber rasises a float which in turn pushes the needle intothe seat. As the fuel level in the chamber lowers (due to comsumption) the needle lowers and allows fuel to enter the chamber. This allowsthe fuel level to remain suffecient and constant under all operating conditions. The height of fuel within the chamber is adjustable by bendinga tab on the float.The float chamber is also equipped with a ventilation system. Refer to Emission Control Systems for description of the Float Chamber Ventilation (FCV) system.

h Altitude Compensator Solenoid Valve (Fed. Only)



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HAC System

POSE

Leans fuel mixture when vehicle operates above approximately 3000 ft.



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Component Locations

ATIONAir passage is integral part of carburetor. Solenoid is on R.H. side of firewal.

RATIONWhen the vacuum/pressure sensor detects atmospheric pressure of 670 mmHg (26.38 in.Hg) or less, the EFC System control unit opens thehigh altitude compensator (HAC) solenoid valve to correct for the richer air/fuel ratio at high altitudes. The HAC valve then permitsadditional air into the carburetor auxiliary air passage near the main metering passage to lean out the mixture.

omatic TransmissionPOSERaises engine speed in responsed to added electrical and A/C load.



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Idle Up Control Linkages And Diaphragms

A/C Idle Up Control Device

LICATIONModels without A/C

Use diaphragm and linkage on carburetor to raise idle in response to added electrical load.Models with A/C

Use diaphragm and linkage on carburetor to raise idle in response to added electrical load.An air by-pass diaphragm on the carburetor to raise idle speed due to A/C compressor load. Fast Idle Control Device (FICD).

ATION^ Idle-up solenoid is on the firewall near the brake master cylinder.^ Fast Idle Control Device (FICD) solenoid is on the firewall near the windshield wiper motor.

^ Idle-up actuator is on the carburetor, near choke linkages.^ FICD actuator is on the front of the carburetor body.

RATIONElectrical load idle-up actuator.

When the ECU energized the solenoid, vacuum is allowed to the diaphragm of the actuator. The diaphragm moves the rod which in turnmoves the likages opening the throttle valve.

A/C load idle-up actuator.When the A/C relay is energized, the signal to the compressor is also conducted the FICD solenoid. When the solenoid is energized,vacuum is allowed to act upon the diaphragm of the FICD. The FICD opens a passage in the carburetor secondary circuit. Air is allowed

past the throttle plate, increasing idle speed.

nual Transmission



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Idle-up Control

POSERaises engine speed in responsed to added electrical and A/C load.

Diaphragm Functions

LICATIONModels without A/CUse diaphragm (A) for increasing idle speed for electrical load.Models with A/CUse diaphragm (B) for increasing idle speed for electrical load, diaphragm (A) for increasing idle speed due to A/C load.

ATION^ Idle-up solenoid is on the firewall near the brake master cylinder.^ Fast Idle Control Device (FICD), A/C idle-up solenoid, is on the firewall near the windshield wiper motor.^ Idle-up actuator is on the carburetor.


RATIONFICD and idle up actuator have two stroke funtions with one diaphragm.^ When (A) portion of adjusting screw is subjected to vacuum pressure, the rod moves toward the direction of the arrow.

And then, as the center sheet of the diaphragm touches the end of adjusting screw 1, the vacun line closes. Accordingly, the rod does notlift more than S1.

^ When nipple (B) is subbjected to vacuum pressure, the rod moves toward arrow direction by S2. And then, the stopper attatched directly tothe diaphragm touches the inner wall of the actuator.As S2 is larger than S1, the center sheet of the diaphragm remains in contact with adjusting screw 1.The remainder between S2 and S1 is absorbed by the stroke change of spring 1 located between the diaphragm and the sheet.



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w SystemPOSE

Provides a means for providing the correct A/F mixture during engine idle conditions.

ATIONAn integral part of the carbuetor.

Fig. 2a Slow Fuel System

RATIONRefer to Fig. 2a for air and fuel supply.

Fig. 2b Slow System

STRUCTIONRefer to Fig. 2b for component designation.

n SystemPOSE

Provides a means for providing the correct A/F mixture during engine cruise conditions.



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Fig. 3a Main System


Fig. 3b Main System


elerator Pump SystemPOSE

Provides a means for providing the correct A/F mixture during engine acceleration conditions.




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Fig. 4a Accelerator Pump System


Fig. 4b Accelerator Pump System


p SystemPOSE

Provides a means for providing a smooth transition between primary circuit and secondary circuit operation.




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Fig. 6a Step System


Fig. 6b Step System


n SystemPOSE

Provides a means for providing the correct A/F mixture during engine cruise conditions.




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Main System


Fig. 3b Main System




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buretor: Service and Repair

Precautions

Wash all parts in clean gasoline and blow dry with compressed air.Use new gaskets, cotter pins and lock plate.Use wrenches and screwdrivers of proper size to prevent damaging parts.Use petroleum jelly to lube all internal O-rings.Use silicone grease to lube external linkages and shafts.

Assembling Choke Chamber

Fig. 17

Install float chamber vent solenoid with new O-rings.

Fig. 18

Install primary and secondary slow air bleeds.Install duty solenoid valve. Apply a light film of petroleum jelly to the O-ring.

Fig. 19

Install needle seat with washer.Install float with needle valve and float shaft.



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Fig. 21

Install idle speed adjusting screw and spring.Install adjusting plate, lever, washer, sleeve, etc. onto the throttle shaft.Tighten nut.

Mating Float and Throttle Chambers

Fig. 22

Place float chamber top side down.Install new gasket.Install screws and tighten.Install throttle return spring.

NOTE: Check that both throttle valves operate smoothly.

Install mixture screw, spring and case. Seat screw and turn out two (2) turns for temporary adjustment. Do not install concealment plug.

Fig. 23

Connect secondary diaphragm rod to throttle valve shaft.Turn float chamber right side up.Install injector weight.Install accelerator pump check ball and spring (closed end of spring faces ball).

nstalling Choke ChamberInstall anti-diesel switch with plunger, spring and washer.Place new gasket on float chamber.Carefully install choke chamber onto float chamber.

NOTE: Make sure choke linkage is aligned properly and there are no wires between the choke and float chambers.



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Install wire clamps and tighten screws.

nstalling Linkage

Fig. 24

Install fast idle cam connecting rod with washers and new cotter pins.

Fig. 25

Connect accelerator pump connecting rod to pump lever by inserting the rod end into hole in pump lever.Install pump lever shaft screw, plain washer and spring washer.

Fig. 26

Install idle-up actuator.

NOTE: Turn the idle adjusting screw in, opening the throttle valve. This will keep the throttle valve from scoring the throttle bore whentightening nut.



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Fig. 28

Install throttle return spring.



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Fig. 29

Connect vacuum hose to main vacuum diaphragm.Route wires according to illustrationMake sure all linkages move smoothly.

Cold Fast Idle

Fig. 31

Manually hold choke valve closed.Open throttle to allow the fast idle adjustment screw to rest on top step of fast idle cam.

Fig. 30

Using a wire gauge, adjust the fast idle screw until clearance G1 is as indicated in illustration.

Vacuum Break (Choke Pull-Off)



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Fig. 31

While holding choke valve closed, open and close throttle to "set" choke.Release choke valve. If valve does not stay closed, drill out the rivets on the bi-metal spring assembly and adjust. Install new rivets.With choke valve closed, connect a vacuum pump to the main main vacuum diaphragm.

Fig. 32

Apply vacuum until the diaphragm moves completely.Using a wire gauge, measure clearance "R" (distance between choke valve and throttle bore) while lightly holding choke valve against lever

"5" .

CLEARANCE "R"0.063 in (1.6 mm)

If necessary, adjust clearance by bending pawl at end of lever.

Secondary Interlock



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Fig. 33

The primary and secondary throttle valves are interlocked so that the secondary throttle valve starts to open when the primary throttle valve isopen to a certain degree. This opening angle of the primary throttle valve and the clearance should be adjusted as illustrated.

Precautions



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Fig. 7 Carburetor (Exploded View)

Use the following procedures in order of appearance.Use wrenches and screwdrivers of proper size to remove nuts and screws.Keep disassembled parts in order not to mix them up when reassembling.Use clean gasoline and compressed air to clean jets and passages.NEVER USE WIRE OR CLOTH TO CLEAN PARTS.

Removing Linkage



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Fig. 10

Remove throttle return spring.

Fig. 11

Remove dash pot.

Fig. 12

Remove idle-up actuator.

Fig. 13

Remove pump lever shaft screw, pump lever, washer and spring washer.Separate accelerator pump connecting rod and and pump lever.Leave rod connected to throttle drum.Remove cam connecting rod, cotter pin and washer.

Removing Choke Chamber



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Fig. 14

Disconnect vacuum hose from main vacuum diaphragm.Remove choke chamber screws and detach choke chamber and gasket from float chamber.CAUTION: Do not damage duty solenoid or float assembly.Remove accelerator pump piston return spring, check ball (in bottom of pump cylinder, under spring) and brass injector weight.Remove anti-diesel switch from float chamber.

Separating Float Chamber and Throttle ChamberRemove cotter pin of secondary diaphragm.Disconnect secondary diaphragm rod from secondary throttle valve shaft.

Remove screws securing throttle chamber to float chamber and separate throttle and float chambers.Remove gasket.

Disassembling Choke Chamber

Remove accelerator pump boot and piston.Remove float shaft, float and needle valve.

Fig. 15

Remove duty solenoid wires from connector.a. Remove rear holder from connector.

b. Pry up pawls of connector with pin removal tool.c. Pull wires out of connector.



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Fig. 16

Remove duty solenoid valve.Remove primary slow air bleed.Remove secondary slow air bleed.Remove float chamber vent solenoid and O-ring.

Disassembling Float ChamberRemove primary main air bleed.Remove secondary main air bleed.Remove primary plug and primary slow jet.

Remove secondary slow jet.Remove lock plate, float chamber drain plugs and primary and secondary main jets.

Disassembling Throttle Chamber

Mixture Screw Plug



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Idle Mixture Adjustment

Using a 1/8" drill bit, drill through the mixture screw plug.

CAUTION: Do not allow the drill bit or screw to contact the mixture screw. Damage to the carburetor or mixture screw will result.

Screw a metal screw into the hole.Using two screwdrivers, GENTLY pry the plug out of the holder.Remove the mixture screw, spring and O-ring (if equipped).Remove nut and disassemble throttle drum.

a. Keep the parts in order. b. Be careful not to damage the throttle shaft or valve.

Remove the idle speed adjusting screw.

ectionCAUTIONSisassembled components should be washed in clean gasoline prior to inspection.articularly small holes and hollows such as fuel passages must be blown with compressed air to remove debris.o not use wires or drill bits to clean passages.

KE CHAMBERir hornCheck for cracks, damage on mating surfaces, damage on threads and excessive wear on choke valve shaft contact areas.hoke valveCheck for deformation and rust.

hoke valve shaftCheck for wear and twist.ower pistonCheck for smooth operation.loatCheck for deformation, damage of seat and stopper and wear of float shaft holes.eedle valveCheck for damage and correct seating of valve.ilter Check for deformation and damage.ir bleed Check for damage on thread and groove.hoke springCheck for rust and deterioration.ccelerator pump bootCheck for crack and damage.uty solenoid valveCheck for deformation and damage and wear or tear of O-ring.

AT CHAMBERloat chamber bodyCheck for cracks, damage on mating surfaces, damage on threads and excessive wear on auxiliary valve shaft hole and wear of accelerator pump cylinder.njector weightCheck for damage and proper seal on seating surface.allCheck for damage or pitting.iston return springCheck for tension, deformation and rust.etCheck for damage on threads and enlarged or clogged holesmulsion tubeCheck for damage on threads and enlarged or clogged holescceleration pump pistonCheck for damage or wear.

OTTLE CHAMBERhrottle chamber bodyCheck for cracks, damage on mating surfaces, damage on threads and excessive wear on throttle valve shaft hole.hrottle valveCheck for deformation and looseness.hrottle valve shaftCheck for binding, wear, twist and damage to threads.dle mixture screwCheck for damage to tip, threads and screwdriver slot.prings



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Check for tension, breaks and rust.

ERWasher

Check for deformation and damage.inkageCheck for damage and wear on sliding surfaces.assagesCheck for obstruction.

allationInstall carburetor and tighten fasteners.Connect accelerator and transmission (if equipped) cables.Connect harness connector.Connect FCV, primary and secondary main air bleed hoses.Connect idle-up solenoid hoses.Connect main diaphragm, distributor and canister vacuum hoses.Connect fuel delivery and return hoses. Install air vent hoses.Install air cleaner.Refer to Adjustments and adjust A/F mixture and idle speed.

movalRemove air cleaner.Disconnect fuel delivery and return hoses. Remove air vent hoses.

Disconnect main diaphragm, distributor and canister vacuum hoses.Disconnect idle-up solenoid hoses.Disconnect FCV, primary and secondary main air bleed hoses.Disconnect harness connector.Disconnect accelerator and transmission (if equipped) cables.Remove carburetor fasteners and remove carburetor.

moval and Repair Noteslways follows steps in numerical order or from top to bottom.se only clean gasoline and compressed air to clean carburetor parts.isconnect negative battery terminal to prevent spark or possible engine starting.lways use new gaskets, O-rings and cotter pins.



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wl Vent Solenoid: Testing and Inspection

Float Chamber Ventilation Solenoid Valve

Check resistance between "+" and "-" terminals. If not between 16.2 and 19.8 ohms, replace valve.Check resistance between "+" or "-" terminal and ground. If not 1M ohms or more, replace valve.Check that the vacuum passage opens and closes while applying current. If not, replace valve. When current is "OFF," spring pressure opensthe passage between "A" and "B." When current is "ON," the passage between "A" and "B" is closed.

Float Chamber Vent Solenoid Schematic

A faulty float chamber ventilation solenoid will set code 25 in the on-board diagnostic system. Refer to the schematic diagram and test thesolenoid with the diagnostic chart.


L: BlueB: Black Y: YellowG: GreenR: Red W: WhiteBr: BrownLg:Light greenGr: Gray



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Float Chamber Vent Solenoid Diagnostic Chart

AT CHAMBER VENTILATION SOLENOID DIAGNOSTIC CHART



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buretor Float: AdjustmentsRemove air cleaner.Remove choke chamber.

Fig. 34

Fig. 35

Adjust float as follows:a. Place top side of choke chamber down.

b. Slowly lower float until the valve stem touches the float seat.c. Measure clearance "H" to check if it is the specified value. If it is not, adjust clearance "H" by bending portion "P" of the float seat.

Clearance "H":

0.437 in (11.1 mm)

d. Raise the float up until float drop stopper "Q" touches.e. Measure clearance "A" to check if it the specified value. If it is not, bend float stopper portion "2" .

Clearance "A":1.835 in (46.6 mm)

Install accelerator pump and boot.



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ke Pull-off: Adjustments

Fig. 31

While holding choke valve closed, open and close throttle to "set" choke.Release choke valve. If valve does not stay closed, drill out the rivets on the bi-metal spring assembly and adjust. Install new rivets.With choke valve closed, connect a vacuum pump to the main main vacuum diaphragm.

Fig. 32

Apply vacuum until the diaphragm moves completely.Using a wire gauge, measure clearance "R" (distance between choke valve and throttle bore) while lightly holding choke valve against lever"5" .

CLEARANCE "R"0.063 in (1.6 mm)

If necessary, adjust clearance by bending pawl at end of lever.



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at Bowl Air Vent Valve: Testing and Inspection

Float Chamber Ventilation Solenoid Valve

Check resistance between "+" and "-" terminals. If not between 16.2 and 19.8 ohms, replace valve.Check resistance between "+" or "-" terminal and ground. If not 1M ohms or more, replace valve.Check that the vacuum passage opens and closes while applying current. If not, replace valve. When current is "OFF," spring pressure opensthe passage between "A" and "B." When current is "ON," the passage between "A" and "B" is closed.

Float Chamber Vent Solenoid Schematic

A faulty float chamber ventilation solenoid will set code 25 in the on-board diagnostic system. Refer to the schematic diagram and test thesolenoid with the diagnostic chart.


L: BlueB: Black Y: YellowG: GreenR: Red W: WhiteBr: BrownLg:Light greenGr: Gray



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Float Chamber Vent Solenoid Diagnostic Chart

AT CHAMBER VENTILATION SOLENOID DIAGNOSTIC CHART



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ottle Plate - Carb.: Adjustmentsd Fast Idle

Fig. 31

Manually hold choke valve closed.Open throttle to allow the fast idle adjustment screw to rest on top step of fast idle cam.

Fig. 30

Using a wire gauge, adjust the fast idle screw until clearance G1 is as indicated in illustration.



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ottle Plate - Carb.: Adjustmentsondary Interlock

Fig. 33

The primary and secondary throttle valves are interlocked so that the secondary throttle valve starts to open when the primary throttle valve isopen to a certain degree. This opening angle of the primary throttle valve and the clearance should be adjusted as illustrated.



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hpot: Adjustments

Dash Pot

Warm up engine to operating temperature and ensure idle speed is within specifications.Under no load condition, turn throttle lever by hand and increase engine speed until end of dashpot is off throttle cam.Gradually return throttle lever and note engine RPM when throttle cam contacts end of dashpot.If engine RPM is not 2300 ± 100 , loosen locknut on dashpot, turn dashpot until desired RPM is reached and tighten locknut securely.Accelerate engine and ensure idle speed returns correctly as throttle is released.



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pipe Restrictor: Testing and Inspection

Using the special tool, confirm that it will not enter the fuel filler inlet.If the tool enters, replace the fuel filler inlet (fillpipe restrictor).



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pipe Restrictor: Service and Repair

Fuel Filler Pipe

Remove rear seat.Remove trim cover.Remove filler pipe cover.Open fuel door and remove two (2) screws.Remove filler hose clamps.Remove filler from body and then remove from hose.Install in reverse order.



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l Filter: Description and Operation

Fuel Filter

POSEFilters dirt and sediment, and to some extent, seperates water from the fuel.

ATIONIn front of the L.R. tire, under the vehicle.

STRUCTIONThe fuel filter uses a low pressure, cartridge design. It has a filter element built into the plastic case. Fuel flows from the permimeter of theelement to the interior of the filter, then to the carburetor.



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l Filter: Testing and InspectionOVAL

Fig. 21

Remove 3 flange bolts and remove filter/pump bracket. See Fig. 21 .Disconnect fuel pump electrical connector.

Fig. 22

Disconnect hoses from fittings A and B. Cap off hoses to prevent fuel spillage. See Fig. 22 .

Fig. 24

Disconnect hose at D. See Fig. 24 .Remove filter.

ECTION

Inspect filter for dirt or water sediment.If filter is clogged or cracked, or if replacement interval has been reached, replace filter.If water is found in filter, shake filter with inlet facing down to expel water (inspection of the fuel tank is advised).

ALLATION

Insert filter into hose at D. See Fig. 24 .



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Fig. 25

Turn ears of clip as shown. See Fig. 25 .Connect hoses at A and B. See Fig. 22 .

Fig. 28

Connect fuel pump electrical connector. Do not allow harness to sag under vehicle. See Fig. 28 .

Fig. 29

Fasten filter/pump bracket to body and torque fasteners to 5.3 - 5.6 ft lb (7.2 - 7.6 Nm).



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Fig. 30

Fig. 31

Using Fig. 30 and Fig. 31 , confirm hoses are connected and routed correctly.



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l Filter: Service and RepairOVAL

Fig. 21


Fig. 22


Fig. 24

Disconnect hose at D. See Fig. 24 .Remove filter.

ALLATION

Insert filter into hose at D. See Fig. 24 .

Fig. 25



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Turn ears of clip as shown. See Fig. 25 .Connect hoses at A and B. See Fig. 22 .

Fig. 28


Fig. 29

Fasten filter/pump bracket to body and torque fasteners.

TORQUE VALUE5.3 - 5.6 ft.lbs (7.2 - 7.6 Nm)

Fig. 30



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Fig. 31




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l Pump: Description and Operation

Fuel Pump And Filter

POSESupplies fuel to the carburetor.

ATIONUnder the L.H. side of the vehicle, in front of the rear tire.

RATIONWhen the fuel pump coil is energized by intermittent pulses (8 to 12 Hz) generated in a completely sealed electronic circuit. The plunger operates in a reciprocating motion which provides pumping action to discharge fuel. Flow rate of fuel changes as plunger stroke varies with

pressure on delivery side, regardless of the number of vibrations of plunger. Therefore, the pump discharges only the required quantity.

STRUCTIONThis fuel pump is a non-disassembling, non-contactor type with a solenoid plunger pump.



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l Pump: Testing and Inspection

Wiring Diagram

Diagnostic Chart



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Diagnostic Chart



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Diagnostic Chart



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l Pump: Service and RepairOVAL

Fig. 21


Fig. 22


Fig. 23

Disconnect hose at C . See Fig. 23 .Remove fuel pump fasteners and remove pump.

ALLATION

Insert pump into hose at C . See Fig. 23 .



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Fig. 26

Attach fuel pump to bracket. See Fig. 26 .

Fig. 25

Turn ears of clip as shown. See Fig. 25 .

Fig. 27

Connect hoses at A and B. See Fig. 22 and Fig. 27 .

Fig. 28



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Fig. 29

Fasten filter/pump bracket to body and torque fasteners. See Fig. 29 .


Fig. 30

Fig. 31



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l Pump Relay: Description and Operation

Instrument Panel Electrical Components

POSEControls fuel pump operation.

ATIONUnder the L.H. side of the dash, next to the ECU.

RATIONThe EFC System control unit provides the power supply and ground circuit to operate the fuel pump relay. When the ignition is switched "ON" with the engine not running, the control unit energizes the relay, thereby operating the fuel pump. After 3 seconds, the control unitshuts off power to the relay unless it receives the crank angle signal (engine cranking or running). A faulty fuel pump relay does not set atrouble code.



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l Return Line: Description and Operation

Fuel Lines

POSERoutes fuel between the fuel tank and engine.

RATION AND LOCATIONFuel is supplied to the engine, and returned to the tank through steel fuel line running along the bottom of the vehicle. Where connections aremade, low pressure fuel hose and steel clamps are used.



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l Return Line: Service and Repair

Fuel Lines

Loosen clips on hose and tube at front and rear of center pipe. Cap hose leading to tank to prevent fuel spillage.Remove the following:^ Heater ^ Carpet^ side sill cover ^ Rear seat^ Fuel filler pipe cover Remove three clamps securing pipe to firewall and remove grommet from firewall.Remove five clamps securing pipe to front pillar and side sill. Remove grommet from bulkhead.Remove tubing.Reverse order to install.



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l Tank: Description and Operation

Fuel Tank

POSEStorage container for fuel.

ATIONUnder the rear of the vehicle

STRUCTIONHouses the fuel gauge sending unit. The fuel tank cap incorporates a valve that prevents fuel vapors from escaping as well as allowing air todisplace the fuel as it is used.



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l Tank: Service and Repairl Tank Draining

Fuel Line Removal

Raise vehicle on hoist.Disconnect and drain fuel through fuel delivery hose.



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l Tank: Service and Repairl Tank Removal and InstallationOVAL

Disconnect negative battery cable.Remove rear seat back and bottom cushions.Remove L.R. sill and side trim.

Fig. 7

Remove fill pipe cover.

Fuel Separator And Rollover Valve

Remove separator tank and rollover valve and separate tube (between tank and separator) from separator by moving clip out of its place.Remove access hole cover and disconnect fuel gauge sending unit connectors.

Fig. 9

Disconnect filler hose from tank (keep hose attached to filler pipe).Disconnect air vent hose at filler pipe.Locate filler pipe grommet under floor.Raise vehicle on hoist.



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Fig. 10

Drain fuel via delivery tube.Remove two (2) parking brake fasteners.

Fig. 21

Remove fuel pump bracket.Disconnect hoses between tank and fuel filter and between tank and return pipe.

Fig. 12

Remove six (6) fuel tank fasteners.Slide tank forward and to the left to clear muffler and remove.

ALLATIONConnect both evaporation tubes at fuel tank.Clamp evaporation tubes located at upper surface of tank.

Fig. 14

Insert filler and air vent pipes of fuel tank into grommets.Install fuel tank with fasteners.



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Fasten filter/pump bracket to body and torque fasteners. See Fig. 29 .


Fig. 30

Fig. 31

Using Fig. 30 and Fig. 31 , confirm hoses are connected and routed correctly.Connect fuel sending unit electrical connector and install cover.Insert grommet into floor.NOTE: If the grommet is installed incorrectly, water leakage may occur.Connect filler and vent hoses.Install fuel separator.Install filler pipe cover, inner trim and seat.Install parking brake.



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l Filler Hose: Service and Repair

Fuel Filler Pipe

Remove rear seat.Remove trim cover.Remove filler pipe cover.Open fuel door and remove two (2) screws.Remove filler hose clamps.Remove filler from body and then remove from hose.Install in reverse order.



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Up Control Valve: Description and Operationomatic TransmissionPOSE

Raises engine speed in responsed to added electrical and A/C load.


A/C Idle Up Control Device

LICATIONModels without A/C

Use diaphragm and linkage on carburetor to raise idle in response to added electrical load.Models with A/C

Use diaphragm and linkage on carburetor to raise idle in response to added electrical load.An air by-pass diaphragm on the carburetor to raise idle speed due to A/C compressor load. Fast Idle Control Device (FICD).

ATION^ Idle-up solenoid is on the firewall near the brake master cylinder.^ Fast Idle Control Device (FICD) solenoid is on the firewall near the windshield wiper motor.^ Idle-up actuator is on the carburetor, near choke linkages.^ FICD actuator is on the front of the carburetor body.

RATIONElectrical load idle-up actuator.

When the ECU energized the solenoid, vacuum is allowed to the diaphragm of the actuator. The diaphragm moves the rod which in turnmoves the likages opening the throttle valve.

A/C load idle-up actuator.When the A/C relay is energized, the signal to the compressor is also conducted the FICD solenoid. When the solenoid is energized,vacuum is allowed to act upon the diaphragm of the FICD. The FICD opens a passage in the carburetor secondary circuit. Air is allowed

past the throttle plate, increasing idle speed.



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the diaphragm touches the inner wall of the actuator.As S2 is larger than S1, the center sheet of the diaphragm remains in contact with adjusting screw 1.The remainder between S2 and S1 is absorbed by the stroke change of spring 1 located between the diaphragm and the sheet.



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Up Control Valve: Testing and Inspection-Up Solenoid Valve

Idle-Up Solenoid Circuit

A faulty idle-up solenoid will set code 24. Refer to the schematic diagram and test the system with the diagnostic chart.


L: BlueB: Black Y: Yellow

G: GreenR: Red W: WhiteBr: BrownLg:Light greenGr: Gray

Idle-Up Solenoid Diagnostic Chart

-UP SOLENOID DIAGNOSTIC CHARTS



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Idle Up System Diagnostic Chart (Code 62)

Idle Up System Diagnostic Chart (Code 63)

-UP SYSTEM DIAGNOSTIC CHARTS



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o-Way Check Valve: Description and Operation


POSEPrevents fuel from flowing into the canister in the event of vehicle rollover.

ATIONIn L.R. 1/4 panel.

RATIONThe valve is constructed of passages and check balls. When the vehicle valve is tilted, the check balls cover the passages, preventing fuelflow through the valve.



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o-Way Check Valve: Description and Operation


POSEPrevents fuel from flowing into the canister in the event of vehicle rollover.

ATIONIn L.R. 1/4 panel.

RATIONThe valve is constructed of passages and check balls. When the vehicle valve is tilted, the check balls cover the passages, preventing fuelflow through the valve.



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o-Way Check Valve: Testing and Inspectionlover Valve, Fuel Tank

Roll-Over Valve

Connect hose to rollover valve as shown.While blowing through the hose, tilt valve at least 90° left and right from normal position. Make sure air flows through valve.Air should not flow through valve when it is tilted further than 90°.



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o-Way Check Valve: Testing and Inspectiono-Way Valve

Two-Way Valve

Blow through the canister side of the valve. Air should pass with slight resistance. If not replace valve.Blow through the fuel tank side of the valve. Air should pass with slight resistance. If not replace valve.Visually inspect the valve and replace if cracks or other problems are detected.



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o-Way Check Valve: Service and RepairOVAL

Disconnect negative battery cable.Remove rear seat back and bottom cushions.Remove left rear sill and side trim.

NOTE: On 5-door MPFI model, rollover valve is on right side.

Fig. 7

Remove fill pipe cover.


Remove seperator tank and rollover valve and seperate tube (between tank and seperator) from seperator by moving clip out of its place.

ALLATIONUse reverse order for installation.



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ottle Full Open Switch: Adjustments

Fig. 12 Accelerator & Throttle-position Switch Adjustment

Fig. 13 Accelerator & Throttle-position Switch Fault Chart

fer to Fig. 12, when checking accelerator switch or throttle-position switch adjustment.e accelerator switch should turn on .12-.28 inch from the accelerator pedal released position. The throttle position switch should turn on4 inch from the accelerator pedal released position. If either switch functions beyond specified ranges refer to chart, Fig. 13.



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mputers and Control Systems: Description and Operationtem Description

Computerized Engine Controls (EFC System)

POSEThe vehicle ECU and sensor and output systems control virtually all aspects of engine operation. This combined control allows the engine tofunction at optimum performance while maintaining exceptable emission and fuel economy levels.

RATIONDuring normal vehicle operation, the ECU controls fuel, spark and emission systems. The system uses the following inputs and outputs tocontrol engine performance and reduce emissions:

INPUTS OUTPUTSEngine rpm Radiator fanEngine temperature Vacuum line control solenoid Manifold vacuum A/C compressor Atmospheric pressure Duty solenoid valveA/C request EGR solenoid Radiator fan Cansiter purge control solenoid



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Vehicle speed Float chamber vent control solenoid Clutch switch (FWD M/T) Fuel pump relayCrank angle sensor Auto choke relayEGR temperature sensor Ignitor / Power transistor Key on Idle-up solenoid Starter on High altitude compensator solenoid Lighting system Upshift indiactor light (M/T)Torque signal (A/T)



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mputers and Control Systems: Description and Operationsting Fuel Cut (CFC) System

POSEImproves fuel economy by closing the slow speed circuit (uses anti-diesel solenoid) in the carburetor during coasting.

ATIONOn right side of carburetor body.

RATIONThe coasting fuel cut (CFC) system activates the carburetor anti-dieseling switch during deceleration, closing the slow system fuel passage.The EFC System control unit detects deceleration when the following conditions are met:^ Intake manifold vacuum is below 590 mmHg (23.23 in.Hg) when the A/C is "OFF" and below 490 mmHg (19.29 in.Hg) when the A/C is

"ON."^ Vehicle speed is at least 40 km/h (25 mph).^ Engine speed is at least 1800 rpm.

When the control unit determines that the vehicle is decelerating, current to the anti-dieseling switch is interrupted, stopping fuel flowthrough the slow system passage. When coolant temperature is below 80° C (176° F), the control unit will not signal the system to stop fuelflow.



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ine Control Module: Description and Operation

EFC Closed Loop System

POSEThe Electronic Fuel Controlled (EFC) Carburetor Control Unit is a digital computer with three main functions:^ Judging the rich or lean state of the air/fuel ratio according to the oxygen sensor output voltage.^ Sending control signals to the carburetor duty solenoid valve to make mixture adjustments according to oxygen sensor output voltage and

information input from various other sensors (feedback control).

^ Fixing control signals under specific driving conditions such as cold starting.ATION

The ECU is located behind the left side of the dash board.

RATIONWhen the EFC Control Unit is sending fixed signals without regard to oxygen sensor output voltage, the system is said to be in "open loop."Conversely, when the control unit is computing signals based on oxygen sensor voltage, the system is said to be in "closed loop."

The EFC Control Unit has built-in preprogrammed values that it will default to if system malfunctions are detected. This usually permits thevehicle to be driven until repairs are made, although performance will be affected.

The EFC Control Unit has a self-diagnostic function that stores trouble codes in its memory. A "Check Engine" light alerts the driver to seek service. A technician can then extract trouble codes from memory which indicate where system problems have occurred and make necessarycorrections.



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ine Control Module: Testing and Inspectionomatic Transmission

gnostic Check

Diagnostic Connectors

NOTE: Never connect or disconnect the control unit or any sensors with the ignition "ON" unless specifically instructed to do so by a testprocedure. Failure to follow this precaution could result in damage to electronic components.

While there is no specific test for the EFC System control unit, nor does it set a trouble code if a fault occurs in its own circuitry, many of thecomponent tests lead to the control unit if no other problems are detected. However, by entering the self-diagnostic "Read Memory" and "D-Check" modes, it is possible to detect certain control unit malfunctions.

Control unit problems can also result from power supply and ground circuit problems. Therefore, these should be checked as well if a faultycontrol unit is suspected.

D MEMORY MODE

Connect "Read Memory" connectors, leaving "Test Mode" connectors disconnected.Turn ignition switch "ON."If "Check Engine" light flickers (normal condition), disconnect "Read Memory" connectors and enter "D-Check" mode.If any trouble codes are stored, "Check Engine" light should illuminate and codes will displayed by the oxygen monitor LED lamp on the

control unit. Confirm code(s) and proceed to "D-Check" mode.If the light does not illuminate at all, it is not a problem with the self-diagnostic function. A problem in the lamp circuit or control unit isindicated. If installing a new lamp that is known good does not correct the problem, proceed to step #6.Turn ignition switch "OFF" and disconnect "Re

subaru justy l3-1.2 2wd carb repair

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