Originally Posted by Wharbone
To test your fast idle valve, take off your intake. There is a hole on the inside of the throttle body.
When your car is cold, there should be suction at that hole. Put your finger over the hole to check. When your car is warmed up, there shouldn't be any suction. If there is, you need to either buy a new one or screw in the plunger.
You would use brake/carb cleaner on your IACV screens if they are gunked up.
I've read a bunch of searches and almost everyone said the FITV was when it's cold and still warming up. During that time it stay at about 2,200 rpm and when it warms up it drops to 1,500 now and does the eratic jumping.