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 (HPFP leaking fuel into oil)
- Cam timing
- Cylinder compression
- Exhaust leaks before or near HO2Ss.
Special Notes
- For the Tiguan with the 2.0T DGUE engine that has one or more of the following fault codes, please see TSB 054615 for possible ECM update and hardware update.
- P0172, P0300, P0301, P0302,P0303, P0304, P0441, P0456, P060C, P2440 and/or P2450