System Too Rich During Cylinder Deactivation Bank 1
During cylinder deactivation on bank 1, the fuel trim of the active cylinders runs persistently rich. Indicates excess fuel delivery or injector leakage.
Affected components
- Fuel injectors
- Deactivation solenoids
- Intake system
Common causes
- High likelihood: Injector leak on active cylinders
- Medium likelihood: Deactivation partial - residual combustion
Possible symptoms
- Check engine light on
- Increased fuel consumption
- Black smoke from exhaust on acceleration
- Smell of unburned fuel, fouled spark plugs
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
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.