2002 GP/GT Troubleshooting Stall/Rev Engine

[DreamRiver]

Hello,

Joined this forum because it looks like you have some good advice on here. I have a 2002 Grand Prix GT. The other morning on the way to work (it was cool out) the heater fan suddenly pulled down, engine was idling normally, continued driving, got to my destination and smelled a "hot plastic smell" when exiting the car. Got off work, drove about 15 minutes, without warning the engine suddenly died. Was missing terribly and would not stay running. So I sat on the side of the road with hood open, so obviously it cooled down some. Started back up and drove a block, seemed fine, pulled over turned the engine off and called for someone to follow me home. When I started it again, ran fine for a few minutes, got out to shut the hood and heard a loud air sucking noise coming from the engine for 2-3 minutes, then egine revved on it's own. I could also smell a sulfur smell from the exhaust.

On the way home (about 20 miles) I watched the tach and just kept the RPMS up to keep it running. We replaced the air filter, and fuel filter which did nothing to change it, put in a new throttle body positioning sensor which also did not help. Mechanics want to charge $80.00 to diagnose the problem in addition to the fix. Still the engine/throttle races and then it stalls, but only when getting to full running temp.

Any Ideas?

[richtazz]

There is a very good chance you have a bad converter. There is a bulletin regarding 01-02 Grand Prix's where the factory converter substrate breaks off and clogs the exhaust. Symptoms include what you're describing, and usually don't show until the car is warmed up.

[DreamRiver]

Hi, I should have mentioned it's been a while, but I had the converter replaced while it was still included in the warrenty for such. The original was bad, it caused the car to lose power and almost felt like the tranny was slipping, but it was not. The engine did not race however, and the voltage didn't drop.

[DreamRiver]

Hi, Just to let you know the electrical system checked and ground wire cleaned and put back on. Didn't solve the problem either. Husband taking it to Advance Auto Parts for a scan but I was told their codes aren't very specific? Any thoughts on that?

[tblake]

If you can get the specific code P0xxx and post it here we should be able to help you pinpoint the issue.

[richtazz]

This sounds like a failing MAF sensor to me, but posting the codes Adv. pulled would help eliminate guessing.