Severity: Fix within days. Drive with caution and watch for new symptoms.
The computer measured more exhaust gas flowing back into the engine than it commanded, which usually means the EGR valve is stuck open.
Clean the EGR valve and passages, test the valve, and replace it if it stays open.
The engine may idle rough or stall. Drivable with care.
You can drive short distances carefully; watch for worsening symptoms. The engine may idle rough or stall. Drivable with care.
The most common causes are: EGR valve stuck open; Carbon holding the valve open; Failed EGR position sensor; Faulty EGR control solenoid. A scan tool and a visual check of the parts above is where a technician starts.
Clean the EGR valve and passages, test the valve, and replace it if it stays open.
