Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car has sensors that tell it how much you're pressing the gas pedal. If these sensors don't agree with each other, your car might not know how fast you want to go.
The P2138 code indicates a problem with the correlation between the voltages of the two throttle position sensors or pedal position sensors. The sensors are not providing consistent data to the engine control module (ECM).
The throttle/pedal position sensors/switches D and E are responsible for sending voltage signals to the ECM to indicate the position of the throttle or pedal. If the ECM detects that the voltage signals from these sensors do not correlate, it triggers the P2138 code. This can be due to a malfunction in one of the sensors or an issue with the wiring or connectors.
• Reduced engine power
• Check Engine Light is on
• Unresponsive or erratic throttle response
• Faulty throttle position sensor
• Faulty pedal position sensor
• Wiring issues or poor connections
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the throttle and pedal position sensors for proper operation.
• Replace the faulty throttle or pedal position sensor.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Toyota Camry
• Regularly inspect and maintain the throttle and pedal sensors.
• Keep the electrical connectors clean and free of corrosion.
• Perform periodic diagnostic checks.
Sensor Issue
• Avoid driving the vehicle until the issue is resolved.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with your vehicle manufacturer for warranty coverage on sensors.
The P2138 code has been commonly reported in vehicles with electronic throttle control systems.
Moderate – This issue can affect drivability, so it should be addressed promptly.
Driving with a malfunctioning throttle or pedal sensor can be dangerous. Address the issue as soon as possible to ensure safe vehicle operation.
• Vehicle in park or neutral
• Engine running
The throttle position sensor is located on the throttle body, and the pedal position sensor is near the accelerator pedal.
Q: Can I drive my car with a P2138 code?
A: It's not recommended to drive with a P2138 code as it can lead to reduced engine power and unsafe driving conditions.
Q: How do I clear a P2138 code?
A: After repairs, you can clear the code using an OBD-II scanner. However, ensure the issue is resolved before clearing the code.
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