Originally Posted by in2pro

Throttle Body Cleaning

Caution: Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.
Notice: Do not insert any tools into the throttle body bore in order to avoid damage to the throttle valve plate.

1. Remove the air cleaner outlet duct. Refer to Air Cleaner Resonator Outlet Duct Replacement.
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.
Notice: 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.
5. Perform the Throttle Learn Procedure. Refer to Throttle Learn.


Throttle Body Removal
Important: The intake manifold, throttle body, fuel injection rail, and fuel injectors may be removed as an assembly. If not servicing the individual components.

1. Remove the electrical wire harness connectors from the throttle body.
2. Remove the throttle body nuts and bolts.
3. Remove the throttle body.
4. Remove the throttle body gasket.
5. Discard the gasket.


Throttle Body Installation
Important: DO NOT use the throttle body gasket again. Install a NEW gasket during assembly.
1. Install the throttle body gasket to the intake manifold. Align the locating tab of the gasket with the notch in the manifold.
2. Install the throttle body , bolts and nuts.
3. Tighten the throttle body nuts and bolts to 10 N•m (89 lb in).

Throttle Learn
The engine control module (ECM) learns the idle position of the throttle plate to ensure the correct idle. Anytime the throttle body is cleaned or replaced, the ECM must learn the new throttle position. The idle may be unstable or a DTC may set if the throttle position is not learned.
Conditions for Running the Throttle Learn Procedure

• DTCs P0101, P0102, P0103, P0107, P0108, P0111, P0112, P0113, P0506, and P0507 are not set.
• The engine speed is between 450-4,000 RPM.
• The manifold absolute pressure (MAP) is greater than 5 kPa.
• The mass air flow (MAF) is greater than 2 g/s.
• The ignition 1 voltage is greater than 10 volts.
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 speed DTCs. 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 at speeds above 70 km/h (44 mph) with several decelerations and extended idles.
After the dive cycle, the engine should be idling normally. ⇒ If the engine idle speed has not been learned, turn OFF the ignition for 60 seconds and repeat step 1.
Once the engine speed has returned to normal, clear DTCs.