98 lumina stalls at operating temp! help plz

hello. my 98 lumina runs perfect until the 3.1 engine operates at operating temperature, this is when my problem occours.:banghead: what happens is the car starts to chug and eventually stalls. i try to start the car after it stalls but the car will only stay running if i keep cranking the engine. if i wait a minute to let the car cool a bit then it will start with no problem, until it is warm again, then it stalls. i had a technician read the computer and found no codes. i had the fuel filter, air filter and oil changed and still had this problem so continued and checked the fuel pump pressure. the fuel pump seems to be fine but the car still chugs at operating temp. the technician cant tell me why this is happening :screwy:and reccommended we replace one part after the next. i cannot afford to do that so im hoping someone knows what im talking about and could help me with my problem

Welcome to AF, Not a good sign when an on site tech cannot fix your car, kinda leaves us here in cyber space somewhat handicapped. When it dies someone has to check for spark and /or scan it for cranking rpms on the scanner, this is basic diagnostics. Theses 2 checks will point you in a direction where we can offer better advice, besides find another tech. Maybe he has already done this?

it seems that this is a mysterious problem. ive checked for spark and there is no problem with that. the car runs perfect until it reaches normal operating temp. at idle the car chugs a little bit. when i give it gas it chugs poorly and stalls. i thopught the fuel pressure may be the cause but the pressure is within GM specifications. anyways thanks for the help. hopefully someone in cyber world has had this problem and can help me with it.

hi. today i took the car to the dealership. they located the problem to a wire harness grounding out on metal. the technician i previously talked to worked at canadian tire. for an hour labour at the dealer my problem is fixed. imagine even changing 1 part at canadian tire $$$ and all it was is a harness grounding out. just alone i was told to do oil change, air filter and fuel filter that i did not even need. canadian tire is a scam!!!!

Just the other day my wife's ZX2 laid down and started running on 2 cylinders and dying when you stop at a light. Intermittantly it would run fine, no logic to it.

I was doing my cursory check of the electrics (first thing I always do with phantom problems) and found that when I put a little pressure on the coilpack's wiring plug, the engine would start missing. I pushed the plug in and held it firmly while twisting on the wires going to it a bit, which caused it to stall.

There was a connector inside the plug coming apart. I was able to cut a plug off another car at the yard and the problem is solved.

But then I started thinking about how much consternation this could have caused in a different situation. An owner might have taken it someplace, got sold a coil and ignition module, left about $400 at that shop and still had the problem a couple of days later, gone back and had more misguided work done, etc...heard plenty of horror stories where people spent arguably more than the car was worth trying to solve a simple problem like this, but nobody bothered to start with the basics.

Moral? Checking connections, grounds, and wiggling wiring harnesses is the FIRST place to start when faced with demons...

I have the same problem what part of the wiring harness was grounding can it be something different?

I have the same problem what part of the wiring harness was grounding can it be something different?:banghead: ME TOO..ITS IN A SHOP BECAUSE I SPENT 2 DAYS TRYING TO FIND THE PROBLEM DID A SCAN,AND GOT NOTHING,I READ SOMEWHERE IT COULD ALSO BE AN IGNITION SWICHOR POWER RELAY TO THE ECM IM STILL WAITING TO FIND OUT ON MY CAR,HOPFULLY NEXT WEEK I WILL KNOW AND I WILL POST WHAT WAS FOUND

check the harnesses from the crank sensors to the ICM. There's one CKPS behind the harmonic balancer, and one in the back of the block.

THE ONE ON THE BACK OF THE BLOCK WAS CHANGED TODAY,WASNT IT.WHEN I LEFT THE SHOP THEY WERE CHANGING THE ONE BEHIND THE BALANCER,EVENTHOUGH IT WAS SCANED AND HAD NOT ONE CODE,I WILL WAIT AND SEE WHAT HAPPENS,,:eek: