Exhaust Gas Recirculation System Performance
The ECU monitors EGR flow indirectly through MAF, MAP or differential-pressure feedback and finds that actual EGR flow does not match the commanded value over a sustained period.
Affected components
- Egr valve
- Egr cooler
- Egr diff pressure sensor
Common causes
- High likelihood: Carbon buildup in EGR passages
- High likelihood: Sticking EGR valve
- Medium likelihood: EGR differential pressure sensor fault
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
- Reduced-power or limp mode may occur
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.