incidence of malfunctions and tampering and in-use ... for environmental research and technology. 2...
TRANSCRIPT
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1
Incidence of Malfunctions and Tamperingand In-Use Emissions for
Heavy-Duty Diesel VehiclesCalifornia Air Resources Board
September 5, 2007
Presented By:
Tom Durbin
Kent Johnson, Wayne Miller, Theodore Younglove*, Matthew Smith*
University of California, RiversideBourns College of Engineering
Center for Environmental Research and Technology
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2
Project Motivation
• On-going regulations expected to significantly reduce NOx and PM from new heavy-duty diesel vehicles (HDDVs) /on-road trucks
• For existing trucks California has an existing program but it monitors only smoke opacity– Heavy Duty Vehicle Inspection and Periodic Smoke Inspection
Program • CARB needs
– understand the incidence of malmaintenance and tampering in HDDVs)
– develop a program to control emissions from in-use HDDVs. • CARB has conducted several pilot studies in this area.
– In an earlier Measure 17 or M-17 program, 109 vehicles
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3
Emissions Breakdown by Class of Truck
0
20000
40000
60000
80000
100000
120000
140000
160000
180000
200000
# Ve
hicl
es
Urban BusesSchool BusesHH Duty(T6) Medium-Heavy Duty Trucks(T5) Light-Heavy Duty Trucks 2(T4) Light-Heavy Duty Trucks 1(T3) Medium Duty Trucks(T2) Light Duty Trucks 2(T1) Light Duty Trucks 1
0
50
100
150
200
250
300
350
400
450
Run
ning
Exh
aust
NO
x (to
ns/d
ay
Urban BusesSchool BusesHH Duty(T6) Medium-Heavy Duty Trucks(T5) Light-Heavy Duty Trucks 2(T4) Light-Heavy Duty Trucks 1(T3) Medium Duty Trucks(T2) Light Duty Trucks 2(T1) Light Duty Trucks 1
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4
Emissions Breakdown by Model Year (Class 8)
0
20
40
60
80
100
Cum
ulat
ive
NO
x Pe
rcen
t
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
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5
Current Project
• Included several elements designed to better understand in-use emissions, malmaintenance, and tampering
• Review records of malmaintenance/tampering– Warrenty records, inspections, other surveys
• Testing of in-use HDDVs under on-road conditions in Stockton– 5 HDDVs tested with the CE-CERT Mobile Emissions
Laboratory (MEL)
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6
Tampering and Malmaintenance Records
• Literature Review• Visual Inspections• Warranty Records• Independent repair shop records• Roadside survey • Electronic monitoring/downloads
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7
Malfunction and Tampering Rates – 1994-1997Defect Radian EFEE
Injection Timing Advanced 5% 3%
Injection Timing Retarded 3% 3%
Minor Injector Problem 15% 20%
Moderate Injector Problem 10% 10%
Severe Injector Problem 4% 3%
Puff Limiter Mis-Set 0% 4%
Puff Limiter Disabled 0% 4%
Max Fuel High 3% 3%
Clogged Air Filter 8% 16%
Wrong/Worn Turbo 5% 8%
Intercooler Clogged 5% 5%
Other Air Problems 8% 8%
Mech. Failure 2% 2%
Excess Oil Consumption 5% 2%
Electronics Failed 5% 5%
Electronics Tampered 15% 10%
Catalytic Converter
Removed 0% 0%
EGR Stuck Open 40% 0%
EGR Disabled 0% 0%
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8
Malfunction and Tampering Rates – EMFAC2007
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9
Heavy-Duty Vehicle Inspection Program• 5,210 records from 1998 to 2002• Inspectors pull over trucks expected to have problems
Database Year 1998 1999 2000 2001 2002Number of Vehicles 890 1346 1361 1042 775
-2
0
2
4
6
8
10
12
Popu
latio
n Pe
rcen
t
65 70 75 80 85 90 95 100Model Year
RoadsidePopulationPercentClass8PopulationPercent
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10
Roadside Inspection Results – 1998-2002 Roadside Inspection EMFAC Group Observation Percent
EGR 19 Pass 5.3%EGR Not Applicable 91.5%
Modified 0.4%Disconnected 1.4%
Missing 1.3%ACI 12 Pass 45.1%
Air Control Indicator Other Air Not Applicable 54.4%Modified 0.2%
Disconnected 0.0%Missing 0.3%
CMPTR 15 or 16 Pass 5.4%Computer Electronics Failed Not Applicable 93.9%
Electronics Tampered Modified 0.1%Disconnected 0.1%
Missing 0.5%PCV 12 Pass 97.0%
Other Air Not Applicable 0.0%Modified 0.7%
Disconnected 1.1%Missing 1.1%
TAC 12 Pass 93.4%Thermostatic Air Cleaner Other Air Not Applicable 0.6%
Modified 0.3%Disconnected 0.9%
Missing 4.8%AAIR 12 Pass 93.9%
Auxilary Air Other Air Not Applicable 1.0%Modified 0.5%
Disconnected 2.0%Missing 2.6%
FUELINJ 3,4,5 Pass 93.1%Fuel Injection Not Applicable 6.4%
Modified 0.4%Disconnected 0.0%
Missing 0.1%
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11
Warranty Repair Data – 1993-1999 • Warrenty claims must be reported when > 1% or 25 engines/vehicles in
an engine family
Defect This study EFFE 1. Injection Timing Advanced <1% 3% 2. Injection Timing Retarded <1% 3% 3. Minor Injector Problem 1.7% 20% 4. Moderate Injector Problem 22.95% 10% 5. Severe Injector Problem <1% 3% 6. Puff Limiter Mis-Set NA 2% 7. Puff Limiter Disabled NA 4% 8. Max Fuel High <1% 3% 9. Clogged Air Filter <1% 16% 10 Wrong/Worn Turbo* 59.0% 8% 11 Intercooler Clogged <1% 5% 12 Other Air Problems <1% 8% 13 Mech. Failure 1.6% 2% 14 Excess Oil Consumption <1% 2% 15 Electronics Failed 64.5% 5% 16 Electronics Tampered <1% 10% 17 Catalytic Converter Removed NA 0% 18 EGR Stuck Open <1% 0% 19 EGR Disabled <1% 0% * 8% without 1997
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12
Non-fleet Repair Facility Records • Results based on survey from a single repair facility
Defect Number This study
EFEE
1. Injection Timing Advanced 30 6% 3% 2. Injection Timing Retarded 20 4% 3% 3. Minor Injector Problem 80 16% 20% 4. Moderate Injector Problem 40 8% 10% 5. Severe Injector Problem 20 4% 3% 6. Puff Limiter Mis-Set 0% 4% 7. Puff limiter disabled 0% 8. Max Fuel High 10 2% 3% 9. Clogged Air Filter 20 4% 16% 10. Wrong/Worn Turbo 10 2% 8% 11. Intercooler Clogged 15 3% 5% 12. Other Air/fuel Problems 10 2% 8% 13. Mech. Failure/ 60 12% 2% 14. Excess oil consumption 70 14% 15. Electronics Failed 55 11% 5% 16. Electronics Tampered 10 2% 10% 17.Catalytic Converter Removed 5 1% 0% 18. EGR Stuck Open 0% 0% 19. EGR Disabled 0% 0%
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13
Roadside Driver Survey• 58 HHDV drivers in 2002• Drivers asked if they had experienced any problems in past 12 months
Defect This study EFEE 1. Injection Timing Advanced 3% 2. Injection Timing Retarded 3% 3. Minor Injector Problem 7.8% 20% 4. Moderate Injector Problem 3.9% 10% 5. Severe Injector Problem 3.9% 3% 6. Puff Limiter Mis-Set 0% 4% 7. Induction problems 2.0% 8. Max Fuel High 3% 9. Clogged Air Filter 7.8% 16% 10. Wrong/Worn Turbo 3.9% 8% 11. Intercooler Clogged 3.9% 5% 12. Other Air/fuel Problems 7.8% 8% 13. Mech. Failure/ 2.0% 2% 14. Valve lash 3.9% 15. Electronics Failed 0% 5% 16. Electronics Tampered 10% 17.Catalytic Converter Removed 0% 18. EGR Stuck Open 0% 19. EGR Disabled 0% Throttle delay 2.0% Other 9.8%
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14
Electronic Scan Tool Survey• Downloads of Engine ECM data• Can determine if engine reflashed to “non-standard” personality• 7 vehicles – 6 no changes – 1 reflashed to factory setting• Speed and RPM distributions
Percent Time by Speed
0.0%
5.0%
10.0%
15.0%
20.0%
25.0%
0-4
10-14
20-24
30-34
40-44
50-54
60-64
70-74
Percent Time
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15
Summary/Conclusions – Malmaintenance & Tampering
• Reviewed about 7,000 records• Warranty Repair (998) incident levels comparable to
EMFAC (except higher for fuel injectors, turbos, & electronics)
• Visual inspections (5,210) indicated visible tampering (<1%)• Roadside survey (78) malfunctions comparable to EMFAC• Repair facility (500) records – comparable to EMFAC
• Overall, decided that current EMFAC tampering/malmaintenance factors were adequate
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16
In-use Emissions Testing
• Testing of 5 HDDVs near Stockton, CA– 1996-2004, various manufacturers
• Testing conducted using CE-CERT’s MEL• Varying operating conditions
– Highway cruise, lower speed cruise, surface streets, power lugs
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17
Test Fleet
Year Engine Chassis Odometer(miles)
1996 Cummins M-11 Freightliner 337,024 2000 Caterpillar C-15 Freightliner 17,826 2002 Detroit Diesel Series 60 Freightliner 181,328 2003 Mack AC427 Mack 107,567 2004 Cummins ISM International 7,664
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18
Test RouteFigure 1. Map of In-use Test Route
HDIML Laboratory
Segment 4
Segment 3
Segment 2
Segment 1
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19
Mobile Emissions Laboratory (MEL)Mobile Emissions Laboratory (MEL)
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20
Mobile Emissions Laboratory (MEL)Mobile Emissions Laboratory (MEL)SchematicSchematic
Diluted Exhaust: Temperature, Absolute Pressure, Throat ∆P, Flow.
Gas Sample Probe.
Secondary Dilution System* PM (size, Mass).
Drivers Aid.
CVS Turbine: 1000-4000 SCFM,Variable Dilution.
Gas Measurements: CO2 %,O2 %, CO ppm, NOx ppm, THC ppm, CH4 ppm. Other Sensor: Dew Point, Ambient Temperature, Control room temperature, Ambient Baro, Trailer Speed (rpm), CVS Inlet Temperature.
Engine Broadcast: Intake Temperature, Coolant Temperature, Boost Pressure, Baro Pressure, Vehicle Speed (mph), Engine Speed (rpm), Throttle Position, Load (% of rated).
Dilution Air: Temperature, Absolute Pressure, Throat ∆P,Baro (Ambient), Flow, Dew Point (Ambient).
Secondary Probe.
GPS: Pat, Long, Elevation, # Satellite Precision.
Exhaust: Temperature, ∆P (Exhaust-Ambient), Flow.
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21
NOx Emissions
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
EMFAC B
ase
EMFAC 40
mph
EMFAC 60
mph
55Cru
ise99
40Cru
ise1
40NoC
ruise
40Cru
ise2
55NoC
ruise
55Cru
ise60
nocruise
60Cru
ise65
nocruise
65Cru
ise70
cruise
Hammer
Rd.PowerL
ug1PowerL
ug2N
Ox
Emis
sion
s (g
/mi)
1996 CUM/M112000 CAT/C152002 DDC/Series602003 Mack/AC4272004 CUM/ISM
SR-99 Freeway
Surface Streets
I-5 Freeway
Surface Streets
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22
NOx Emissions – Fuel Specific
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
55Cru
ise99
40Cru
ise1
40NoC
ruise
40Cru
ise2
55NoC
ruise
55Cru
ise60
nocr
uise
60Cru
ise65
nocr
uise
65Cru
ise70
cruis
eHam
mer R
d.Power
Lug1
Power
Lug2
NO
x Em
issi
ons
(g/k
g fu
el)
1996 CUM/M112000 CAT/C152002 DDC/Series602003 Mack/AC4272004 CUM/ISM
SR-99 Freeway
Surface Streets
I-5 Freeway
Surface Streets
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23
PM Emissions
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
EMFAC Base EMFAC 55mph
55Cruise99 Hammer Rd. 55Cruise99 Hammer Rd.
PM E
mis
sion
s (g
/mi)/
NO
x Em
issi
on (g
/(50*
mi)) 1996 CUM/M11
2000 CAT/C152002 DDC/Series602003 Mack/AC4272004 CUM/ISM
PM Emissions
NOx Emissions
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24
PM Emissions – Fuel Specific
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
55Cruise99 Hammer Rd. 55Cruise99 Hammer Rd.
PM E
mis
sion
s (g
/kg
fuel
) or N
O x E
mis
sion
s (g
/(100
*kg
fuel
)) 1996 CUM/M112000 CAT/C152002 DDC/Series602003 Mack/AC4272003 Mack/AC427
NOx Emissions
PM Emissions
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25
THC Emissions
0.0
0.5
1.0
1.5
2.0
2.5
EMFAC B
ase
EMFAC 40
mph
EMFAC 60
mph
55Cru
ise99
40Cru
ise1
40NoC
ruise
40Cru
ise2
55NoC
ruise
55Cru
ise60
nocr
uise
60Cru
ise65
nocr
uise
65Cru
ise70
cruis
eHam
mer R
d.Pow
erLu
g1Pow
erLu
g2TH
C E
mis
sion
s (g
/mi)
1996 CUM/M112000 CAT/C152002 DDC/Series602003 Mack/AC4272004 CUM/ISM
SR-99 Freeway Surface Streets
I-5 Freeway
Surface Streets
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26
CO Emissions
0.0
5.0
10.0
15.0
20.0
25.0
EMFAC B
ase
EMFAC 40
mph
EMFAC 60
mph
55Cru
ise99
40Cru
ise1
40NoC
ruise
40Cru
ise2
55NoC
ruise
55Cru
ise60
nocr
uise
60Cru
ise65
nocr
uise
65Cru
ise70
cruis
eHam
mer R
d.Pow
erLu
g1Pow
erLu
g2C
O E
mis
sion
s (g
/mi)
1996 CUM/M112000 CAT/C152002 DDC/Series602003 Mack/AC4272004 CUM/ISM
SR-99 Freeway
Surface Streets I-5 Freeway
Surface Streets
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27
Real-Time Emissions from MEL
1996 Cummins M11 Run #1
0
10
20
30
40
50
60
70
0 500 1000 1500 2000 2500Time (sec)
Velo
city
(mph
)
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
Emis
sion
s (g
/sec
)
Speed mphNOx g/secTHC g/sec x 100CO g/sec
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28
Summary/Conclusions from Emissions Testing• Overall
– Depend on pollutant, vehicle, and driving condition– Real-time emissions: transient /depend on engine operation
• NOx– Some vehicles higher NOx for higher speeds (≥55 mph vs. 40 mph/surface
street) while others did not – The oldest vehicle, 1996 truck, had the highest emissions for nearly all
types of driving • PM
– Surface street driving: oldest vehicle had highest PM emissions – Highway driving: 2 newest vehicles had the highest PM emissions – Some vehicles had higher PM emissions on the surface streets vs. highway– For newer vehicles on highway there appeared to be a NOx/PM tradeoff
• THC– THC emissions generally higher for surface streets and 40 mph cruise
compared to highway driving• CO
– CO generally higher on surface streets vs. highway– CO emissions under steady state generally low (1 -3 g/mi)