Rough idle issure...done a lot.

[SpecialD]

Hi all, first post here.

I have a 92 240sx coupe (97 KA24DE) that i have been having rough idle problems with (idle was jumping up and down randomly in RPM ~900-1700). It began to misfire on the 3rd cylinder (from the front) so gave it a full tune up which didn't fix the problem (needed it anyway). Next i took it into the shop and had all 4 fuel injectors replaced, and they had also noticed that the computer temp sensor was disconnected and broken. So i had them replace that. I also had them clean out the throttle body and adjacent parts, which i was told we're very dirty.

When i got the car back the cylinder was firing again (this was yesterday), but now the car was idling rough in a different way. RPMs seem to be pretty stationary, but now the idle is rough, like i'm on a roller coaster. Also the mechanic tells me the 2nd cylinder doesn't appear to be firing at idle, which i assume is causing the shaking at idle. When i drive it the throttle response is great, vastly improved, which is what the fuel injectors and clean airflow would do, along with all 4 cylinders firing great. The car drives great aside from this rough idle issue, and the fact that car has come back to me with starting problems (which it didn't have when i took it in). The car turns over a lot and i have to push the gas to get it to start pretty much. Also it smells like its running rich.

Any ideas? I'm going nuts over this and i really wanna get this car in good mechanical condition before i start putting parts into it

Modified by SpecialD at 10:16 PM 6/2/2007
Modified by SpecialD at 1:30 AM 6/3/2007