WHY DOES MY CAR IDLE ROUGH? HELP!!!!!!!!!

[J]

I have a 92 base model Lumina with the 3.1 and a few mods. Intake and free flowing muff, besides the muff everything factory is still there. My car idles liie it is spitting and i can feel it in the pedal and just sitting there. When i go to hit the gas it feels like it's going to stall or bog for a sec then takes off. What could this be? I was thinking backpressure but i still have the cat and stock pipe on there. HELP i'm getting really sick of this. Thanks Jay

[gmrulz4u]

Does the bogging/hesitation go away once you've got a steady foot on the gas pedal?

 

If so, it would surely be fuel pressure related.

 

I've come to realize, after having many problems with my Supreme, that everytime you think it's something advanced, like a sensor, electrical/computer related, etc...it always seems to end up being just a part of BASIC engine performance ie. FUEL DELIVERY(injectors, fuel filter, fuel pump), SPARK(coils, module, plugs, wires), and AIR

[J]

i've done every thing i can do, i've had to cut off my old fuel filter and put a new piece of gas line on there and thats fine now, the plugs are brand new. The wires tested fine, i am starting to get pissed. This is how it is, i am at a light and it turns green and i hit the gas then the rpm's drop and it wants to stall for like a half second then it takes off and doesn't happen till the next time i stop and hit the gas. I want to fix it bad and i've heard from o2 sensor to no back pressure from the exhaust, i don't know what to think. Thanks for the input Later Jay

[J]

HELPPPPPPP, could it be doing this cuz the sensor that was plugged into the ait box is now in the middle of the cone on my intake? I think it's a jsut a air temp sensor? help please. Jay

[Guest]

try this. Put you stock airbox back in. If that does not help, check to see if you have a vacuum leak. Leave the stock airbox in so that it can't be caused by that. Just spray some carbcleaner around EVERYTHING THAT COULD HAVE A VACUUM LEAK, and listen to the cars idle. If you spray an area, and the car starts to stutter, or try to die, then you have a vacuum leak. Do this around the throttle body, the duct for the air box, under the plenum, and along every single vacuum line in the car.

 

taylor

[90lumina3.1]

sounds very similar to what mine was doing, only that on mine the idle would drop the second i stopped.. check vac lines and also... if its a vac controlled tranny, my problem was low ATF, so check that too. if not, keep checkin round. the IAT sensor doesnt do much, mines just hanging down in my engine compartment

[J]

i'll check it out over thanksgivin break, thanks Jay