My 2000 grand prix 3.1 sometimes idles fast at startup. sometimes 1500 to 2000 rpm. shutting engine off and on a few times sometimes gets idle to return to normal.
When I disconnect the throttle position sensor when the engine is idling fast, it casues the idle to return to normal. but trying to drive with the TPS unhooked causes the tranny to not shift right.
Is the TPS bad? Thanks.