95 Lumina won't run after warmed up?!?!

I'm working on my inlaws 1995 Lumina sedan, 103000miles, 3.1 liter engine. The car is having a problem with not running after being driven long distances. It will start up (after it has been sitting for a while) with no problem, and it runs great. But if you drive it for more than about 30 minutes and shut it off and try to restart within about an hour it will run a sec then die. Once it sits for a couple hours it will once again, start up run fine. This problem does not occur every time it is driven. It appears that if you start it from a cold condition that it can be run any amount of time and it will run fine, this only occurs after you shut it off and try to restart. The service engine light is not coming on at all. When it is at the point of not starting/dieing, it doesn't seem to fire at all. Is there something common assoc. with a very warmed up engine that is a needed startup condition but does not cause the car to run bad before you shut it off. I am searching forum, but if anyone has an idea, let me know. A buddy suggested the crank position sensor or the ignition module. The crank position sensor was replaced about six months ago by dealership when in laws were exp. same problem. Could be faulty new part or shoddy labor. I am going to investigate these thingsl

Those two items would be my first guess. They seem to go bad around the same time sometimes. In fact, if I still worked in a shop, I'd probably advise customers getting one replaced to do the other as well, just to avoid another problem. Some people will gladly do this, some think you are just trying to hose them.

I think I know exactly what your problem is. I too just went through the exact thing you described. You might want to consider the culprit to be the fuel pump motor. I have a 1996 Lumina that you could start and drive for as long as you wanted without problems, then when you shut if off and tried to start it, it either wouldn't start or when it did it would idle really rough then stall. I had to wait around for 5-10 minutes before it would start. At that point it would start and run fine until you shut it off again. I first thought it to be the crank sensor. Luckily, the motor is replaceable and you don't have to replace the whole fuel pump module. It is in the tank and the tank has to be dropped. While you are at it, you might also consider replacing the fuel filter. Only one thing you have to watch as well when you take the tank down, from the age it is not uncommon for the tank to leak at the straps after you re-assemble and mount the gas tank back in. This is caused from dirt and moisture being trapped between the straps and the tank itself.

Good luck and hope this helped.

Sounds like you have a problem with your ignition coils or ignition control module. These are common symptoms for faulty coilpack or module. I would suggest take off all three coil packs and the module(simple process) and take them to AutoZone where they can test your ignition parts. They can determine if you have a faulty module or a coil pack.