im having a problem with my IACV on my 98 GSR swap it had a bad ground fixed that and now when we plug the IACV in the car revs 1500-2000 when its unpluged the car idles perfect if anyone can help that would be great

 

recheck wiring, and have a known good IACV around also for testing purposes

 

I think you have the wrong plug going in the iacv, also check the map and tps sensor it might be switched.