ok guys, i own a 96 Cavalier Z24, I recently had to swap the engine because the old one gave out. Anyway, when i drive my car in the 1500-2200RPM range the car really seems to put around. What i mean by put is it seems like its backfiring. it doenst just do it once but constantly does it. I just get off the gas let it coast then ease back on to it till it does it again and repeat it. I bought some sea foam and put it in and i got no white smoke, only black and it still has black coming out. Also during idle the car's RPM will bounce from 600-1000RPM. Also forgot to mention when it puts the rpms drop bout 100RPMs and then goes back up to where it was and jsut constantly does that when it puts. I have heard a couple possibilties from friends and stuff but i dont kno which one to start with. I figured someone on here might kno, I have heard this things: Spark Plugs, Oxygen Sensor, Cat Converter, Fuel Pump(i already changed the fuel filter). I just want to hear any other possibilties or if someone knows exactly what it is great, i just need to get it fixed cuz its a pain and im sure not good for the engine. Thanks

Might be one of the censors on the throttle body like the IAC sensor. I had a problem when I put my venom intake manifold on the IAC was touching the metal manifold and heating up and throwing a code. It was also idling somewhat how you described the problem, I hear you can pick them up cheap at wreckers, something cheap to try and pretty easy for you to change yourself.


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Yes officer I knew the speed limit was 50

i concure with coldairintake, check your plugs and wires also


Fast isn't always good, looks and sound is sometimes better

Imamarine

IAC valve on the throttle body.




-da chinchilla

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