P0402 Exhaust Gas Recirculation Flow Excessive Detected
Too much exhaust gas is being recirculated.
Common causes
- Stuck-open EGR valve
- Faulty control solenoid
Symptoms
- Rough idle
- Stalling
- Hesitation
What to check
- Check if the valve closes fully
- Inspect for carbon holding it open
- Check control signal
Manufacturers may add their own detail to generic codes. If your vehicle shows a different description for P0402, follow the service information for that make and model.