I've been fighting a battle with irratic idle for years on my 98 Sunfire GT, and a guy from school was able to hook up a monitor to it to see what the sensors were doing. Once the initial warm up idle came down, my timing was all over the place at idle, going from +25+ down to +10 or more very rapidly. Any ideas what could cause such random timing changes in a quick fashion? I replaced the cams almost 6 years ago with 375 lift and 200 degree duration on both intake and exhaust. I don't normally throw codes unless it's really cold out and the car idles for a very long time (10+ min it'll throw a P0300 code).
I pinched the Map hose and it ran worse. This did start after cams, I did not retune, as was told I didn't have to. I do have a feeling that'll have to happen though.
My guess is fueling is off with the cams and no tune. I have seen bad feuling cause this exact thing. Seeing as you pinched the map hose and it got worse supports this as idle fueling is controlled by map sensor.
FU Tuning
Is it possible to have a bad fuel injector too? Once I'm out of idle, things are fine, and the power really starts to be noticed above 2500 RPM.
I was hoping not to hear that, anyone in the Fort Wayne, IN area who can?
