The computer sees too much EGR flow. The driver may notice rough idle, stalling or hesitation.
Causes vary by car. Test before you order a part.
Likely causes, most common first
- EGR valve stuck open
- Carbon holding the valve open
- Faulty control solenoid
- Faulty EGR sensor
Parts usually involved
- EGR valve Find at suppliers
- Control solenoid Find at suppliers
- EGR passages Find at suppliers
Test before you replace
Check whether the valve seats fully closed at idle and inspect it for carbon.
General guidance for generic OBD2 codes. Always follow the maker's procedure for the car in front of you.