Check Engine Code

P2138

Throttle / Pedal Position Sensor D / E Voltage Correlation

Severity: high DIY difficulty: 2/5 Typical cost: $80–$600

What P2138 means

Drive-by-wire pedals have two redundant position sensors. P2138 means they're disagreeing by more than the ECM allows. Always triggers limp mode.

Symptoms

  • Check engine light
  • Reduced engine power / limp mode
  • No throttle response
  • Stalling

Likely causes (most common first)

  1. Failed accelerator pedal position sensor
  2. Damaged pedal harness
  3. Bad connector
  4. Failed throttle body (correlated sensors)

Can I keep driving?

High — risk of damage if ignored

Typical repair cost

DIY fixes can start near $80 (parts only). Shop repairs for P2138 typically run up to $600 depending on the underlying cause and vehicle. Start with the most common cause — Failed accelerator pedal position sensor — before throwing parts at it.

Related codes

P2122P2123P2127P2128

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