high idle and sputtering

[JM Graphics]

Car: GM S/C Pontiac Sunfire 2.4

Everytime i start the car cold or warm it idles VERY high, goes directly to 2k then either settles down to 900 where it supposed to be or studders and if it doesn't shut off it goes to 900 rpm.

The vac gauge is reading 20 which is what it is supposed to be, so no leaks there. I have changed the tps and iac about 2 times and never made a difference. I even unplugged the iac and it made not one difference, this happens when i put on diff sensors also, new and used.

Seems like everytime im cruising, let off the gas then hit it again softly it cuts out and my aem wideband goes to lean off the charts and then it picks back up.

Wondering if it could need re tuned or what. I'm running a slight tune that had a gm s/c re flash base.

[malloyboy1]

any chance its some kind of idle air control valve?

[05 mazda6s]

clean MAF sensor?

[Metalhedd]

moisture in the distributer cap and rotor can cause cutting out too. that was the case with my car.

[Cardriverx]

my aem wideband goes to lean off the charts and then it picks back up.



lean = spuddering. What is the wideband showing at idle?

Also, my car spudders alittle at cold start, but thats just cuz im running 305cc injectors without much tuneing..

[SovXietday]

How long has it been idling that high at cold start, since you got it reflashed? If so, that's you're problem.

Need more info. Has this just recently started or has it been since the ECU was reflashed.

[JM Graphics]

This has all of a sudden happened. Wondering if a bad MAP sensor could do this because im running a GM 2 bar MAP. I unplugged the battery for a hour and it started up doing the same stuff. The wide band is showing 11.2 at idle before closed loop which is rich as hell.

[ScoobyNubieToo!]

Could be a faulty 02 sensor?