Cylinder 9 Combustion Performance
The closed-loop combustion controller reports that combustion performance on cylinder 9 is below the calibrated quality metric. Computed from the cylinder pressure trace — IMEP (indicated mean effective pressure), CA50 (50% mass burnt angle) or peak pressure deviates from the model.
Affected components
- Cylinder 9 combustion
- Cylinder pressure sensor 9
- Fuel injector cyl 9
Common causes
- High likelihood: Mean effective pressure outside model
- Medium likelihood: Injector flow has drifted
- Low likelihood: Gateway module routing CAN messages incorrectly
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
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.