P1559
Idle Speed Control Throttle Position Adaption Malfunction
Severity
⚠️ MediumCan you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–89 (est.)
Symptoms
- Unstable idle speed
- Stalls at idle
- RPM fluctuates when warming up
- The Check Engine light comes on
- Loss of power when releasing gas suddenly
Causes
- Throttle valve contamination
- Throttle Position Sensor Malfunction
- Open or short circuit in control circuit
- Mechanical failure of the throttle drive
- Engine ECU malfunctions
How to Fix
- Check the condition of the throttle valve and clean if necessary
- Check the integrity of the wiring and connectors
- Diagnose the throttle position sensor
- Perform throttle valve adaptation procedure
- If necessary, replace the throttle assembly