Bank 1 fuel mixture is too lean during off-idle/part-throttle operation.
SYMPTOMS
- Check-engine light
- Hesitation
- Surge
LIKELY CAUSES
- Vacuum/intake leak
- Dirty MAF
- Low fuel pressure
- Faulty injector
DIAGNOSIS STEPS
- Read fuel trims at off-idle
- Smoke-test the intake
- Check MAF and fuel pressure
RELATED PARTS
- MAF sensor
- Intake gaskets