Well... i have a 2.8L V6 MPFI 5 speed... well there are times when my car begins to stumbble.. let me be more specific
The RPM drop to about 500 when im at a stop light and the car feels like its about to shut off.. and if i dont hit the accelerator the "service engine soon" light comes on... But wait.. then there are times when my car revs itself up to about 2000 RPM for no reason when im coming to a stop... Any ideas what it might be?

 

Timing. Vacume leaks, Fuel blockedge (new Fuel filter), Fuel, pump.... It could be alot of things... My car used to do that. I just readjusted my timing and change my cap and rotor.. and it stopped

 

Idle Control Motor. Does it only happen when you are comming to a stop? That would be my guess since you have a stick and anytime you disengage teh clutch with no throttle it want s to go to idle and that's where you are having the problem. TomP tune-up time it is!!!

 

either the IAC or timing. Moe's car was doing this when we put the timing at 14 degrees (from 6!) So we put the timing back some, and it was still doing it. We then changed the IAC and it was fine.

 

IAC is usually what causes this. When was the last time you cleaned the throttle body out. A carbend up TB can do it to, any idea what code your getting? If it somthing to do with TPS it can be a dirty TB and the car will idle up and down in an attempt to self clean.

 

IAC?? thats a new one for me.... thats true its been a while since i cleaned it