P0121High severity

TPS Range/Performance

The throttle position sensor reading is outside expected parameters.

Safe to Drive?
No

Have this diagnosed before driving further

Informational only. Consult a qualified mechanic.

Estimated Repair Cost
$100 - $450
Common Causes
  • Worn TPS
  • Carbon buildup on throttle body
  • Wiring issue
Recommended Action

Clean throttle body and replace TPS if needed.

What does P0121 mean?

The P0121 OBD-II diagnostic trouble code (DTC) indicates: tps range/performance. This is a high-severity powertrain code that your vehicle's onboard diagnostics system triggers when the throttle position sensor reading is outside expected parameters. If your check engine light is on with this code, you should have the vehicle inspected immediately before driving further.

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