P0121
Throttle/Pedal Position Sensor/Switch A Circuit Range/Performance
Generic code
Fuel and Air Metering
High severity
Moderate repair
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What P0121 means
- The fault code P0121 indicates that there is an issue with the circuit of the throttle or pedal position sensor/switch 'A'. This may cause the engine to lack power or even stall.
Possible symptoms
- Reduced engine power or acceleration
- Unresponsive throttle or accelerator pedal
- Stalling or intermittent loss of power
- Illuminated check engine light
Possible causes
- Faulty or damaged throttle or pedal position sensor/switch
- Wiring issues or loose connections in the circuit
- Corroded or dirty electrical connections
- Failed engine control module (ECM)
Related parts
- Throttle Position Sensor: Throttle position sensor generally denotes the position of the accelerator pedal. Problems lead to poor acceleration
Possible solutions
- Replace the faulty throttle or pedal position sensor/switch
- Inspect and repair any damaged wiring or connections
- Clean or tighten any corroded or dirty electrical connections
- Replace the engine control module (ECM) if necessary
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P0121 on OBD DashX
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