P2109 — Throttle/Pedal Position Sensor A Minimum Stop Performance
The ECU detects that the throttle position sensor A signal at the closed-throttle stop does not match the learned minimum value. The mechanical or electrical zero reference of the throttle has drifted out of the expected range, often after cleaning, replacement or wear.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Throttle position sensor
- Throttle body
- Throttle actuator
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- Carbon deposits on throttle plate
- Throttle position sensor drift
- Idle/throttle relearn not performed
Possible symptoms
- Check engine light on
- Reduced throttle response, possible limp mode
- Hesitation or surging
- Idle too high or too low
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
- Reduced-power or limp mode may occur
Related codes
Sources
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.