Well i just started to drive my cavalier for the first time. It does have the 2.4 in it, it has 97,000 miles on it, when it idles it idles ruff, like it has a big cam, when i drive its fine. Ive checked for vaccum leaks and nothing that i can see or hear, and ive blocked the egr valve to see if that was the problem and it wasnt. Ive put fuel injector cleaner in it and didnt seem to help to much. The car could have been sitting for a long time in a junkyard or salvage lot before i bought it?? anybody have any thoughts??? thanks!
scott (section8cav) wrote:define "rough"
when it idles it idles ruff, like it has a big cam
Throttle Position Sensor.
Unhook it and see if it idles better. That sounds like it may be your problem.
I had kind of the same problem. Try holding the throttle at 1000 rpm. If the rough idle becomes rythmic get a squirt bottle with some water and one by one soak the intake manifold at each mating surface to the head for each cylinder. Mine ended up being the intake manifold gasket on the number one cylinder. The water temporarily sealed the leak and my idle smoothed out then got rough again as the water got injested.
I would start with getting the fuel filter changed and cleanout the throttle body first.
their are no vaccum leaks, 50lbs of fuel pressure, i cleaned the throttle body, new spark plugs, ...... still not runnin right???
Same problem... cleaned out IAC and checked mounts. New spark plugs, a/c delcos... still there. Recommened by someone to run it by a shop and clean the injectors (with the cleaner that gets pumped into the rails, not the retarded gas tank additive stuff).
Not sure that's the right route, but for now I got the cruise control cable pinned up /w a cotter pin so it idles at 1000rpm = no shaking. Couldn't find an idle adjust screw.
If it was the fuel filter there would be performance problems /w acceleration and higher RPMS I would think. Guess I'll try pulling the TPS and changing fuel filter as those are the cheapest routes so far.
check your IAC and TPS.
I replaced my intake mani gasket, injector o-rings, and and disconnected the battery to reset the PCM to fix my idle problem.
Desert Tuners
“When you come across a big kettle of crazy, it’s best not to stir it.”
Tried disconnecting the TPS... still rough idle. Is it possible to plug the IAC to see if its the problem or would that just cause it to stall out?
