Hi all,
i bought a 1995 3000gt (manual). There is a problem: i start the car and set off but after a while my car's idle begins to go up and down madly. when i gear neutral my rpm goes between 2000-2500 irregularly it sometimes climbes 3000-3500. After a while it goes normal (i think motor gets warm).
I asked a mechanic and he said possible reason is air valve (i think it is idle air cntroller) is there anybody has an idea?

 

sounds like it could be the iac for sure. my friends stealth was acting the same way you describe and the iac was the problem there.

 

Had the same problem on my 93 VR4. IAC fixed it.

 

i have a 92 VR4 and mine was acting the same way and my car would shut off in between shifts and what happened was a Screw on the top of the throttle body fell off. so turn on the car and put your finger over the throttle body hole on the top and see if it corrects that. and look and see if the screw is there or not.