System Too Rich (Bank 1)
The oxygen sensor in bank 1 detected a rich condition (too little oxygen in the exhaust).
You will more than likely not notice any drivability problems, although there may be a misfire.
A code P0172 may mean that one or more of the following has happened
- The MAF (Mass Air Flow) Sensor is dirty or faulty. Note: The use of "oiled" air filters can cause the MAF to become dirty if the filter is over-oiled.
- Vacuum leak.
- Fuel pressure or delivery problem
- Throttle position sensor