System Too Rich at Higher Load (Bank 2)
Bank 2 fuel trim hits the rich limit only at higher load. Often excessive fuel pressure, a stuck-closed MAF reading low, or coolant temperature signal stuck cold causing over-fuelling.
Affected components
- Fuel pressure regulator
- Mass air flow sensor
- Coolant temperature sensor
Common causes
- High likelihood: Fuel pressure too high
- Medium likelihood: MAF reads low under load
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.