When I started my 8 it was very rough and idle bounced up to almost 3000rpm. It idled very rough almost as if it was going to cut out and idle bounced for a minute or so until engine heated up and settled down to 800rpms. The temperature was warm outside and I just recently changed plugs and air filter. Could it be my coils affecting my start up? Any ideas would be appreciated.

 

When my engine coil went my car wouldnt go over 60 km/hr..sounded like a tractor even after changing plugs and wires. Changed the coil and it was back in action.

 

Thinking more a sensor...vacuum leak...get an OBD11 READER. Best thing I bought, though it doesnt diagnose mecanical..it does misfires etc...about 75.00-100.00.

 

I would also check to make sure you didn't accidentally disconnect a vac line or crack the intake accordion when you were installing the air filter. Stubling idles when cold can also mean a vac leak.

 

I checked the intake/accordion there were no visible cracks. I will look into the possibility of a vac leak.
Thanks

 

I also had idle probs..and could not get higher than 4000 rpm. Did everything I could think of...one day opened my airbox and the short piece of plastic pipe that is screwed on had an crack...got a new one and everything was normAl again..most idle probs are very simple things that miss the eye..also clean your trottle body and maby an smoke test for vac leak...also check al your vac pipes..they brittle after a while..well in some cases

 

It was the IMTV sticking (SSV). I had it all cleaned out and SSV replaced, works like new again