OBD codes / P0402
P0402
ModerateExhaust Gas Recirculation (EGR) Flow Excessive
Get it looked at soon to avoid further wear.
Likely causes
- stuck-open EGR valve
- faulty EGR position sensor
- carbon holding the valve open
Common fixes
- clean or replace the EGR valve
- check the EGR position sensor
Seeing P0402 on your car? Get a diagnosis specific to your exact year, make and model.
Diagnose P0402 for my vehicleGeneric OBD-II reference. Manufacturer-specific behavior varies — confirm with a scan tool and, for safety-related codes, a professional inspection.