My Bronco idles at 1,300 RPM for 60 seconds after first starting cold then drops to 750 RPM in neutral. I then place the vehicle in drive & the engine goes to 1,100 RPM. If I turn the AC on in drive the idle drops back to 750 RPM. If I place the vehicle in neutral the vehicle drops back to 750 RPM also. If I put it back in drive it goes back to 1,100 RPM. There is no check engine light. I have not checked for codes. Could the Idle Air Control Valve be the problem?
Why does my 1990 5.8 Bronco idle at 1,300 RPM after warm up, in gear with AC off on 1990 Ford Bronco