Not an O2 sensor issue. I am leaning towards an idle relearn process that seems to be required after cleaning a throttle body. I found a technical service bulletin with the following procedure and will try it tomorrow. I have not found the proper adjustment procedure for setting the throttle plate screw. Mine has been changed and nowhere is it written how to get it within range so the IAC valve can compensate properly.
Throttle Learn
Important: Do NOT perform this procedure if DTCs are set. Refer to Diagnostic Trouble Code(DTC) List - Vehicle.1. Start and idle the engine in PARK for 3 minutes.2. With a scan tool, monitor desired and actual RPM.3. The ECM will start to learn the new idle cells and Desired RPM should start to decrease.4. Ignition OFF for 60 seconds.5. Start and idle the engine in PARK for 3 minutes.6. After the 3 minute run time the engine should be idling normal.Important: During the drive cycle the check engine light may come on with idle speedDTCs. If idle speed codes are set, clear codes so the ECM can continue to learn.
��
If the engine idle speed has not been learned the vehicle will need to be driven atspeeds above 70 km/h (44 mph) with several decelerations and extended idles.7. After the drive cycle, the engine should be idling normally.
��
If the engine idle speed has not been learned, turn OFF the ignition for 60 secondsand repeat step 6.
8. Once the engine speed has returned to normal, clear DTCs.
