Cold Start EGR B Flow Excessive Detected
During cold start, the ECM detects that EGR channel B delivers more exhaust mass than commanded. Engine smoothness and warm-up calibration may be affected.
Affected components
- Egr valve b
- Egr cooler b
- Egr diff pressure sensor
Common causes
- High likelihood: EGR valve stuck partially open
- Medium likelihood: Actuator overshoots commanded position
Possible symptoms
- Check engine light on
- Pinging or knocking under load
- Power loss and hesitation
- Possible rough idle
- Failed emissions inspection (NOx)
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
Related codes
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.