Same as P0172 for Bank 2 — an over-rich mixture fuel trim cannot fully correct.
SYMPTOMS
- Check-engine light
- Rough idle
- Fuel smell
- Fouled plugs
LIKELY CAUSES
- Leaking injector
- High fuel pressure
- Faulty MAF
- Contaminated O2 sensor
DIAGNOSIS STEPS
- Read fuel trims on both banks
- Check fuel pressure
- Inspect injectors
- Check MAF and O2 data
RELATED PARTS
- Fuel injectors
- MAF sensor
- O2 sensors