P0507Powertrain
Powertrain · SAE
Idle Speed Higher Than Expected
Meaning
Idle RPM is above the value the ECU expects. The idle control system cannot bring the speed back within the threshold, often because of unmetered air entering the engine.
Common causes
- Intake air leaks (hoses, gaskets, brake booster)
- Dirty throttle body or faulty idle valve
- Leak in the vent/EVAP circuit
- Faulty intake manifold gasket
- Throttle cable or plate not seating (mechanical systems)
Symptoms
- High, steady idle
- Check engine light on
- Reduced engine braking on lift-off
- Possible harsh gear engagement when lifting off
Severity
Moderate: it does not strand the vehicle but indicates unmetered air, with worse economy and driveability; a high idle can make stopping less safe.
What to do
- Look for air leaks (spray/smoke) on hoses, gaskets and the brake booster
- Clean the throttle body and check throttle adaptation
- Check the EVAP system and vent lines
- Verify expected throttle opening and airflow values