How to Replace the Throttle Body in a Chevy Avalanche
- 1). Make sure the engine is completely cool and that the ignition is in the OFF or LOCK position. Disconnect the negative battery cable.
- 2). Disconnect the vacuum hose from the throttle body, the harness connectors for the throttle position sensor (TPS) and idle air control (IAC) valve. Take the coolant hoses off the throttle body and the vapor vent pipe.
- 3). Loosen and remove the nuts that secure the throttle body. Lift out the throttle body and the gasket. Discard the gasket. Clean the gasket mating surfaces thoroughly with a plastic scraper.
- 4). Set the new gasket in place and then install the throttle body over it. Set the nuts in place and torque them to 89 inch pounds of torque.
- 5). Connect the coolant hoses to the throttle body and the vapor vent pipe. Reattach the accelerator control cable and the cruise control cable to the throttle body. Connect the TSP and IAC valve electrical connectors.
- 6). Attach the vacuum hose to the throttle body, then install the air intake duct. Check to make sure that the accelerator pedal moves without binding by pressing it to the floor. Release it a few times while the engine is OFF.
- 7). Reset the IAC valve by turning the ignition on for 10 seconds and then turn it off for 5 seconds. Start the engine and test for the correct idle speed.
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