P0402 Exhaust Gas Recirculation Flow Excessive Detected
What does P0402 mean?
P0402 — Exhaust Gas Recirculation Flow Excessive Detected. This is an OBD-II diagnostic trouble code a scanner retrieves when your vehicle's computer detects exhaust gas recirculation flow excessive detected. The level of risk depends on how the vehicle is currently running and how long you've been driving with the light on.
Common causes of P0402
- EGR valve stuck open
- Faulty EGR position sensor reading incorrect
- Stuck-open EGR pintle from carbon buildup
- Wiring or vacuum control fault holding the valve open
- PCM fault
How to fix P0402
- Inspect the EGR valve for sticking in the open position
- Watch EGR position on an OBD-II scanner and command it closed
- Check the EGR control solenoid and wiring
- Clean or replace the EGR valve
- Verify correct EGR flow after repair with a road test and scan tool