95 Mustang GT RPM problem

[Stangasaurus]

Whenever I press the clutch in to shift, it revs up. So, I always have to wait 1.5 seconds to press the clutch in and shift. I think it only happens if I shift below 4,000 RPMs. Also say if I am creeping up in traffic and I press the clutch in to stop in gear, the RPMs rise.

I dont think this happened when I had the stock IAC, but Im not sure since I’ve only had the car for a couple weeks.

 

[jozsefsz]

The IAC will cause your idle to hang. You might need to adjust your idle air bleed and throttle stop since you replaced the IAC. The 'surging idle checklist' found all over this place covers the procedure.