P0403 Code: Exhaust Gas Recirculation (EGR) Circuit Malfunction
🟠 Moderate severity · drivable
Drivable, but the EGR valve can't be controlled, which can affect idle and emissions.
What P0403 means
There's an electrical fault in the EGR valve control circuit, so the computer can't open or close the valve as commanded.
Symptoms
- Check engine light is on
- Rough idle
- Possible stalling
- Failed emissions test
Common causes
- most common: Faulty EGR valve (electrical)
- common: Damaged wiring or loose connector at the EGR valve
- less common: Corroded EGR connector
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Inspect and clean the EGR connector | Yes | $0–10 |
| Replace the EGR valve | Yes | $100–400 |
| Repair damaged EGR wiring | Mechanic | $50–150 |
Frequently asked questions
Can I drive with a P0403 code?
Yes, but the EGR valve can't be controlled, which can affect idle and emissions.
What is the most common cause of P0403?
A faulty EGR valve or a wiring/connector problem.
How much does it cost to fix a P0403?
Typically $100–$400 for a new EGR valve, or less for a wiring repair.
Related codes
P0401
P0401 Code: Exhaust Gas Recirculation (EGR) Flow Insufficient Detected
P0402P0402 Code: Exhaust Gas Recirculation (EGR) Flow Excessive Detected
P0404P0404 Code: Exhaust Gas Recirculation (EGR) Circuit Range/Performance
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.