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)
- Failed accelerator pedal position sensor
- Damaged pedal harness
- Bad connector
- 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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