Engine high idle

Hello,

This sounds like you have throttle actuator that needs to be cleaned but to be sure lets run the codes to see what comes up.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

and if you clean the actuator leave it plugged in.

https://www.2carpros.com/articles/throttle-actuator-service

Check out the diagrams (below). Please let us know what happens.

Throttle Body Cleaning

1. Remove the air cleaner outlet duct. Refer to Air Cleaner Resonator Outlet Duct Replacement (See: Air Cleaner Fresh Air Duct/Hose > Removal and Replacement > Air Cleaner Resonator Outlet Duct Replacement).

Warning

Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.

Caution: Do not insert any tools into the throttle body bore in order to avoid damage to the throttle valve plate.

2. Inspect the throttle body bore and the throttle plate for deposits. You will need to open the throttle plate in order to inspect all surfaces.
Caution: Do not use any solvent that contains Methyl Ethyl Ketone (MEK). This solvent may damage fuel system components.

3. Clean the throttle body bore and the throttle plate using a clean shop towel with GM Top Engine Cleaner, P/N 1052626, or AC-Delco Carburetor Tune-Up Conditioner, P/N X66-P, or an equivalent product.
4. Install the air cleaner outlet duct. Refer to Air Cleaner Resonator Outlet Duct Replacement (See: Air Cleaner Fresh Air Duct/Hose > Removal and Replacement > Air Cleaner Resonator Outlet Duct Replacement).
5. Perform the Throttle Learn Procedure.

Throttle Learn

Reset Procedure (Performed after the throttle body is cleaned or replaced)
1. Ignition ON, engine OFF, perform the Idle Learn Reset in Module Setup with a scan tool.
2. Start the engine and monitor the TB Idle Airflow Compensation parameter. The TB Idle Airflow Compensation value should equal 0 percent and the engine should be idling at a normal idle speed.
3. Clear the DTCs and return to the diagnostic that referred you here.