Throttle/Pedal Position Sensor/Switch A Circuit Malfunction
Common Symptoms
- Check Engine Light illuminated
- Poor acceleration or hesitation
- Engine stalling or idle issues
- Erratic or surging idle speed
- Limp mode or reduced power
- Cruise control inoperative
Most Likely Root Causes
- Faulty throttle position sensor
- Damaged or corroded wiring harness to TPS
- Poor electrical connection at TPS connector
- Failed accelerator pedal position sensor
- Throttle body contamination or carbon buildup
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Component Location
The throttle position sensor is mounted on the throttle body assembly, typically on the throttle shaft opposite the throttle cable or linkage.
Manufacturer Notes
Some vehicles use integrated throttle body assemblies where the TPS is not separately replaceable and requires complete throttle body replacement.
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