Please help! 96 GA Gt 3.1L

[smcdonnell1]

Hello everyone,
I have a 96 Grand am GT with the 3.1 and I am having some problems that I can't seem to figure out. The car runs great until it is warmed up, then the idle starts surging. If I put the car in gear it stops. I have done a tune up, replaced the fuel pump and filter, replaced the icv, seafoamed the intake, replaced all the vac lines, cleaned the egr, and mass air flow, checked the coils,and cleaned the intake itself. It has new intake gaskets as of last year and I am stumped. The only way I can get the surging to stop when not in gear is to pull the pcv out of the valve cover. If I do that the surging stops entirely. I only get codes if I let it surge until it dies. My gas milage is crap by the way. I believe the 2 problems are related but I cant be sure. The engine dies if I cover the end of the pcv with my finger after it is warmed up but not before. Please help! I'm about ready to give up on this car and buy a new one.
Thanks Everyone, Sean

 

[melsg5]

Sounds to me like it is running rich, by blocking the PCV you are preventing air from entering that leans the rich condition. Did you do a fuel pressure test, too high? Other thought is leaky fuel injectors.

 

[smcdonnell1]

Thanks for the help. What you say makes sense about the pcv after reaching temp, however I am begining to believe I have a more serious problem. If I remove the oil cap the engine runs fine. With that being said I believe there is a buildup of pressure inside the engine causing the pcv to close prematurely. If my thinking is right I probably have some worn rings, or valves. Does that sound right? I dont feel a vac comming from the oil fill so this is my best guess. please tell me I am wrong here
Sean

 

[melsg5]

do a compression test and fuel pressure test and I believe you can check injectors also