Genuine Chevrolet Tracker Throttle Position Sensor

Chevrolet Tracker Throttle Position Sensor Parts Questions & Answers

• Sensor,Throttle Position
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  Q: What is the location and function of the Throttle Position (TP) sensor?

  A: The Throttle Position (TP) sensor is located on the throttle body and monitors the throttle valve opening angle. It is a potentiometer that receives a 5-volt reference voltage from the PCM. As the throttle valve opens, a brush moves across a printed resistor board, varying the output voltage. This signal is sent to the PCM, which uses it to determine the throttle valve angle. The TP sensor signal is used by the PCM to control various components such as the fuel injector pulse width, Idle Air Control valve, ignition timing, EVAP canister purge valve, and EGR Valve. If there is a problem with the TP sensor circuit, it will set a trouble code and the PCM will resort to a default value. To check and adjust the TP sensor, disconnect the battery cable and unplug the electrical connector. Check the resistance between specified terminals when the throttle is fully open and closed. If the readings are incorrect, adjust or replace the sensor. For models with throttle body injection, apply vacuum to move the throttle valve to the idle position. Slightly loosen the TP sensor mounting screws and refer to the specified feeler gauge thickness to adjust the sensor. For models with sequential multiport fuel injection, the adjustment process is slightly different. Connect an ohmmeter between specified terminals and adjust the sensor accordingly. Verify continuity between terminals with different feeler gauge thicknesses. Once adjusted, tighten the screws to the specified torque. For 1999 and later models, the resistance between specified terminals should be checked and the sensor replaced if readings are incorrect. To replace the sensor, disconnect the battery cable and unplug the electrical connector. Remove the sensor screws and detach the sensor from the throttle body. When installing the new sensor, ensure that the lugs on the throttle body lever engage their corresponding slots in the sensor pickup lever. Adjust the sensor if necessary and tighten the mounting screws. Plug in the electrical connector and reconnect the battery cable.