MustangVixenGT

Ok, so I am starting to run out of ideas. My car keeps doing this thing where the idle will bounce around a lot on warm starts. However I think that part is fixed but it leads into the next thing....

Took the IAC off and cleaned it out, warm start issue seems to of gone away. However it will still bounce around a bit when the cars at idle. Then today I pulled into a parking space and it dropped to about 500rpm then went back up to normal.

So is this still possibly the IAC? Maybe it's just going bad all together or it could be something else causing this?

corker

A dirty throttle body will cause the IAC to act a little weird - fluctuate at times and cause stalling. Also, check for vac leaks - get an old windex spray bottle and fill with water - spray all vac lines and listen for RPM drop or engine stumble (works well and is a lot safer than using brakekleen!). The water spray on ignition wires will also help pinpoint a bad wire or porous/faulty secondary ignition components.

MustangVixenGT

Awesome thanks, I guess my next step is taking off the throttle body...

cominus

Use carb cleaner, it works the same and probably safer.

robinson209

Clean the MAF sensor?