● Fix soon
Usually drivable for a short time, but check it soon. It can get worse.
Usually drivable for a short time, but check it soon. It can get worse.
The computer cannot control idle speed as expected. The driver may notice high, low or surging idle, or stalling.
Guided check
- Is there a vacuum leak?If yes: Repair it and let the idle relearn as the maker describes.
- Is the throttle body or idle valve dirty?If yes: Clean it, then run the idle relearn.
- Does the idle valve or throttle motor fail its test?If yes: Check the wiring, then replace the faulty part.
These checks are general and are still being reviewed by working mechanics.
Causes vary by car. Test before you order a part.
Likely causes, most common first
- Dirty throttle body or idle valve
- Vacuum leak
- Faulty idle air control valve
- Wiring fault
Parts usually involved
- Idle air control valve Find at suppliers
- Throttle body Find at suppliers
- Intake gaskets Find at suppliers
Test before you replace
Clean and inspect the idle air path, check for vacuum leaks and test the valve or throttle control.
General guidance for generic OBD2 codes. Always follow the maker's procedure for the car in front of you.