damn air going crazy again
 

ive replaced the IAC valve and have taken my NA mk3 to my mechanic a couple of times for the same thing. he left things great, and my car is acting funny again. actually, it runs great after its been warmed up. whenever its cold, the RPM will start going crazy. up to two and back down almost to 0, and continues and will sometimes stall. as soon as the car starts warming up and the temp needle starts going up, then it stops. no air leaks. ive also noticed the car has lost some power.

any suggestions?

oh yeah, is it normal for RPM to be at 1200rpm while at idle? when my car is cold it will be at 1000, maybe 950, then 1200 when warmed.

The normal idle is 700rpm + or - 50.
Check the temp sensor for the computer.