Questions and Answers

Sunbird Cranks, But Not Start - Revisited

Q. I read your reply to my previous question on the 1988 Pontiac Sunbird 2.0L fuel injected (not turbo) vin K. I did the things you said but they did not help. I am still stalling in the morning. Heres what has happened since then.

I have a 1988 Pontiac Sunbird. It stalls only in the morning when it is cool. It will not restart unless I spray engine starter fluid into the air cleaner. It then starts but will stall if I press down on the gas or turn on the air. If I press ever so slightly on the gas the engine will rev up. As I continue to press on the gas ever so slightly more and more it revs to a very high rpm. If I let off and press down quickly it stalls. When it stalls you can always smell a lot of gas fumes under the hood. Seems like it is choking on gas. In the afternoon when it is hot outside (100+ degrees) it runs fine with an occasional hesitation. I have replaced the fuel pump, oxygen sensor, air cleaner temp sensor, coolant sensor and fuel pump relay. Testing shows it to hold its vacuum. Obviously, temperature has something to do with this problem but I cannot think of any other part affected by temperature to replace.

Please HELP!!!

A. This time I have a little better idea of what's going on. I would check into the Throttle Position Sensor (TPS) and Air Flow Meter (AFM). Either one will cause these symptoms as well. There are established test that you can perform on those parts. I would go to the library and look them up in the service manual and you can test them to see which one is bad.