RPMs go up and down on idle?!?!?!?

[solvman]

Hi all,<BR>I have just replace my clutch on '94 GS 2.5...Wird thing happens to me when you start the care RPMs go up to 2,500 for couple of seconds then they drop to 1,000 and go up to 1,500...drop down to 1,000 and go up to 1,500...drop down and go up...it sounds like someone presses gas pedal...When i turn on my A/C everything works fine RPMs get to stay at one place. Any suggestions what might be wrong with my car? BTW, i've tried to ECU, didnt help.

[mazdaspeed002]

Check the IAC valve on the throttle body. Unplug it and if it does the same as it does plugged in, its bad.