The Throttle Position Sensor (TPS) and throttle actuating DC motor are integral to the throttle body. The throttle body is a non serviceable item, replace the throttle body as an assembly.
The throttle blade will not close completely when engine is shut down. This engine off blade position is for start up. The electric throttle body will adjust the throttle blade for idle control as the idle air control valve adjusted idle speed previously on cable actuated throttle bodies. The electric throttle body will also adjust the throttle blade for normal driving operation. The throttle blade will move to the engine off blade position if throttle body codes are set to provide air for limp-in mode.
Removal & Installation
The throttle position sensor and throttle actuating DC motor are integral to the throttle body. The throttle body is a non-serviceable item. The throttle body must be replaced as an assembly. For additional information, refer to the following section, "Throttle Body, Removal & Installation.
- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Throttle Body and the Powertrain Control Module (PCM).
- Look for any chafed, pierced, pinched, or partially broken wires.
- Look for broken, bent, pushed out or corroded terminals.
- Inspect the Throttle Body for any condition that would result in an incorrect signal, such as damage or contamination.
- Inspect and clean all PCM, engine, and chassis grounds that are related to the most current DTC.
- If numerous trouble codes were set, use a wire schematic and look for any common ground or supply circuits.
- For any Relay DTCs, actuate the Relay with the scan tool and wiggle the related wire harness to try to interrupt the actuation.
- Use the scan tool to perform a System Test if one applies to failing component. A co-pilot, data recorder, and/or lab scope should be used to help diagnose intermittent conditions.