2007 sierra sle gmc p0121 fixed idle high

Question

i changed throttle acuator control on 2007 sierra sle gmc , i no longer have check engine light but......my idle is high. i have to put it in drive or reverse then the throttle goes back to 500-700 rpms...do i have to take it to a dealer or what//

Answer 1

No, the idle should adjust it self after driving, but it may take a couple of days to set. If the problem persist after a few days, you may have to have the dealer reprogram the ECM for you.