16556/P0172/000370
From Ross-Tech Wiki
16556/P0172 - System Too Rich, Bank 1
Possible Symptoms
- Irregular behavior
Possible Causes
- Fuel system
- Excessive fuel pressure
- Leaking or contaminated fuel injectors
- Leaking fuel pressure regulator
- Low fuel pressure or running out of fuel
- Vapor recovery system
- Air leaks after the MAF
- Vacuum leaks
- Improper seated engine oil dipstick
- Stuck EGR valve
- Oil overfill
- Cam timing
- Cylinder compression
- Exhaust leaks before or near HO2Ss.