2017 Chevy Malibu P2138 Accelerator Pedal Position

2017 Chevy Malibu


  • 1.5L Turbocharged Inline-4
  • Horsepower: Approximately 160 hp
  • Torque: Around 184 lb-ft


  • 6-Speed Automatic

Fuel Efficiency:

  • City: Approximately 27 mpg
  • Highway: About 36 mpg

Understanding and Resolving P2138 Code on a 2017 Chevy Malibu with the 1.5L Engine

The P2138 trouble code can be a cause for concern when it appears on the diagnostic system of your 2017 Chevy Malibu with the 1.5L engine. In this comprehensive guide, we will delve into the details of the P2138 code, its possible causes, symptoms, and effective solutions to rectify the issue.

What is P2138?

P2138 is a diagnostic trouble code (DTC) that specifically relates to the throttle/pedal position sensor/switch. In simpler terms, it indicates a problem with the communication between the throttle position sensor (TPS) and the pedal position sensor (PPS).


Symptoms of P2138:

  1. Reduced Engine Power:
    • One of the most noticeable symptoms is a reduction in engine power. Your Chevy Malibu may feel sluggish and less responsive.
  2. Stalling or Surging:
    • Stalling or surging while driving, especially at low speeds or when idling, can be a common symptom associated with the P2138 code.
  3. Check Engine Light (CEL):
    • The illumination of the check engine light is a clear indicator that there’s an issue with the throttle and pedal position sensors.

Possible Causes of P2138:

  • Faulty Throttle Position Sensor (TPS): A malfunctioning throttle position sensor can lead to erratic signals being sent to the engine control module (ECM), triggering the P2138 code.
throttle position sensor

The throttle position sensor (TPS) plays a crucial role in the functioning of a vehicle’s engine management system. Its purpose is to monitor the position of the throttle valve and relay this to the engine control module (ECM).

  • Issues with Pedal Position Sensor (PPS): Similar to the TPS, problems with the pedal position sensor can disrupt the communication between the throttle and pedal sensors.
accelerator pedal position sensor

The pedal position sensor (PPS), also known as the accelerator pedal position sensor, is a crucial component in a vehicle’s electronic throttle control system. Its primary purpose is to monitor and relay the position of the accelerator pedal to the engine control module (ECM).

  • Wiring or Connector Problems: Damaged or corroded wiring and connectors can hinder the proper flow of electrical signals between the sensors and the ECM.

Diagnosing P2138:

Before attempting to resolve the P2138 code, it’s crucial to perform a thorough diagnosis to pinpoint the exact cause. This may involve using an OBD-II scanner to retrieve additional trouble codes, checking for loose connections, and conducting a visual inspection of the throttle and pedal position sensors.

Resolving P2138:

  1. Inspect and Repair Wiring/Connectors:
    • Start by examining the wiring and connectors for any visible damage. Repair or replace any faulty components.
  2. Throttle Position Sensor Replacement:
    • If the throttle position sensor is the culprit, consider replacing it with a genuine OEM part to ensure proper functionality.
  3. Pedal Position Sensor Replacement:
    • Similar to the TPS, a malfunctioning pedal position sensor may require replacement to resolve the P2138 code.


Dealing with the P2138 code on your 2017 Chevy Malibu can be a challenging task. But with a systematic approach to diagnosis and the right solutions, you can successfully address the issue. Regular maintenance and timely repairs will contribute to the overall performance and longevity of your vehicle.

If you’re uncomfortable with performing these tasks yourself, it’s advisable to seek professional assistance from a certified mechanic.

By following these guidelines, you can effectively tackle the P2138 code and ensure your Chevy Malibu continues to run smoothly on the road.

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