I have a 91 LS motor in my CRX that keeps reving up at idle.
Its will rev up to 2000 rpm and them back to 1000. Back and fourth
Any ideas???????????

 

My cousin's does the exact same thing. Except his goes to about 3200 RPM, but won't go down unless you blip the throttle. Is it too much tension? A bad sensor? Throttle body need cleaning?

Rob

 

Do you have any codes? Could be IACV, your TPS, fuel filter, MAP sensor. There could be a vacuum leak? There are all sorts of things. The first thing is check if there are any codes.

 

stole the words off of my keyboard

 

there isn't any codes.
which leads me to think its the fuel pump or vacuum leak
any thing else it could be?

 

Yes I have had a similar problem and it was related to the idle speed setting. Warm the car up to operating temperature. Disconnect the IACV. Set the idle to ~750 RPm using the idle adjustment screw on the top rear of the throttle body. Reconnect the IACV. It should fix the problem. If not Set the TPS to 0.5 volts +/- 0.05 at ilde with the ignition on and the car not running. Measure between the center wire and the green/white at the TPS.