P1221
Throttle Position Sensor 1- 2 Correlation
Severity
⚠️ MediumCan you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–67 (est.)
Symptoms
- Rough engine idling
- Dips when pressing the gas pedal
- Check Engine light comes on
- Reduced engine power
- Increased fuel consumption
Causes
- Malfunction of one of the throttle position sensors
- Contamination or mechanical damage to the throttle valve
- Problems with wiring or sensor contacts
- Engine control unit malfunction
- ECU software error
How to Fix
- Check the resistance and output signals of both throttle position sensors
- Inspect the condition of the throttle valve and clean if necessary
- Check the integrity of the wiring and the quality of contacts
- If necessary, replace the faulty sensor
- Diagnose and reflash the ECU if a software error is suspected