2003 Pontiac Sunfire

I posted this in June with little response. Obviously nobody knows what is wrong to include 5 different mechanics and shops. Every time I hit a bump the car dies. It will restart. Mechanic said it was an ignition module. Replaced it and could not reset the computer, and either could the dealer. Said they finally got it reset and when they test drove it, the timing jumped ruining the engine. I might be getting taken here. They suggested a used engine. Installed it and now it will still not run. They say it has something to do with the cam and computer. They can’t figure it out. Any ideas. They had it back to the dealer with no help and another mechanic…no help. Help!! Been in the shop for 4 months. Now they say they must pull the front of the engine…something to do with the cam/computer. Help.

These intermittent issues can just be really hard so its likely there is little response here b/c its even hard when you can lay your hands on the car - let along when you can’t.

The cam thing is probably about the cam position sensor. I don’t know this specific car, but you probably have a cam position sensor at the top end and a crank position sensor at the bottom. Input from these is required by the computer for producing the spark. The relation to bumps seems to indicate some kind of poor/loose electrical issue - a bad sensor or perhaps just a wiring harness or loose ground problem.

If you want folks to really try to provide suggestions (other than “keep hunting”) you’d have to be able to give some specifics about what various shops have done to check things out including any error codes that have been pulled from the computer. Otherwise we just sit here and re-make guessed that your mechanics have already made. See what you can list in terms of basic things that have been tested/excluded. My own approach if no one else could figure it out would be to stand in my driveway for as long as it took with car running while wiggling every last wire I could get my hands on.