TorqueMech OBD Code Guide
P0121 - Throttle/Pedal Position Sensor/Switch A Range/Performance
TPS/APP signal is outside expected range.
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Estimate after confirmation
Code Overview
TPS/APP signal is outside expected range.
Common Causes
- TPS/APP sensor drift
- Throttle body sticking
- Wiring issue
Diagnostic Steps
- Check live data for dropouts
- Inspect throttle plate for carbon
- Verify connector pins tight
Related OBD Codes
Browse nearby codes when systems overlap.
Next Steps
Move from code to checks, then estimate.