Auto 132 Lab Experience Report

Part 1: Vehicle InformationStudent name(s):Mitchell Childs, Jaren Rambo, Melissa Adling

Vehicle year, make, model: 2002 Chevrolet venture

Customer’s concern(s): - Gas mileage is poor. Vehicle seems to hesitate, pause, and then accelerate. Misfire?

Part 2: Documentation Document the steps you took to diagnose and repair the vehicle—in the order that you did them. Write every step—even if you made mistakes and now wish you would have done it differently. Begin when you picked up the keys, end when you returned them. BE DETAILED & INCLUDE PHOTOGRAPHS!

1. First, we took the vehicle out for a test drive. We didn’t have to drive far, we could feel the hesitation as we tried to accelerate and we could tell something was wrong. The check engine light was on and we assumed that was for a misfire as our customer had guessed as well. Nevertheless, we pulled the vehicle into the garage and did a full vehicle visual and fluids inspection to start.

2. The vehicle inspection went fine. All the fluids were in order, but there was some damage to the car that we noticed. There were some scratches and the front right headlight was being held on by a wire that may have once been a coat hanger. Along with these little things, the bottom of the car and especially around the pinch welds (close to the tires) were extremely rusted and fragile. Last of all, the inside panel on the driver’s door was loose. It wasn’t clipped all the way down or something was broken and preventing it from staying as one with the whole door. It just wiggled a bit, so it was nothing to worry about. The horn did not work either. Outside of this, the car was functioning. It just wasn’t the prettiest little van in the world.

3. 4. After our inspection we decided to check the codes that the vehicle was throwing. There were a bunch of

pending codes, but the only one that had to do with engine performance and the only confirmed code was a P0301 cylinder 1 misfire. Just like we had assumed there would be. Just after getting the codes, we noticed an ark jumping through one of the spark plug wires and we immediately knew what the problem was. Bad spark plug wires. So we ordered a new set and got ready to replace them.

5. 6. While waiting for the spark plug wires, Mitchell opened up the fuse box and found the fuse for the horn. It

was blown. So, he replaced it and the horn worked again.

7.8. We started replacing the plug wires one at a time in order to make sure we connected them in the right

places. In this vehicle, we couldn’t reach the back 3 spark plugs, so the first thing that we tried doing was removing the rocker arm bolts and rocking the engine forward in order to reach over the top and around the back side to pull the plug wires. This would not have worked if we didn’t have Melissa with us. She was the only one of us who could fully get her arm through the gap and pull the plugs, but they still proved to be stubborn and difficult to pull out. After fighting for a while and getting some help from Parker (he also managed to get his arm over the top and help pull plugs) we were finally able to get a plug out and brake the other one off so that a small end of it was still stuck over the top of the spark plug. After playing with that and trying to get that, we gave up on this method and decided to try getting to it from under the car.

9. 10. We put the car on a lift, dropped the engine a bit, and reached up through the bottom of the car. This still

proved to be a challenge and took a while before we were finally able to get some vise grips over the stuck piece and pull it off. With that off we were able to replace that spark plug wire and finally pull off the last spark plug wire and replace it as well. Once this was done, we secured the front spark plug wires to make sure that they would not get destroyed by any other engine parts. After that, we were able to get the car

down and take it for a little test drive and everything worked fine. There was no more hesitation and no more misfire.

11.

Part 3: Reflection & Analysis

What parts of this process went well? The part of the process that went well was replacing the front spark plug wires. They were easy to reach and remove.

Which steps were most critical in your diagnosis process?The most critical part of the diagnostic process was the finding the ark that was jumping out of the spark plug wire that lead to cylinder 1.

What kept you from being as effective as you could have been?I think the most difficult part was our struggle to reach the spark plug wires in the back. If we knew what would have worked best before-hand, we could have saved some time in getting to the rear plugs. I also think that the spark plug wire breaking was a setback as well. It took a lot of time trying to reach without damaging other parts of the vehicle or ourselves.

Now that you can look back on how this project unfolded, what would you like to do differently next time?Next time, I believe that it would be important to ensure that we have the proper tools and that we analyzed our options as to how we were going to approach the problem before we jumped into it.