P0172

Test 1 - 4:

Test 5 - 7:

Test 8 - 10:

Test 11:

SYMPTOM
P0172-FUEL SYSTEM 1/1 RICH

WHEN MONITORED
With the engine running in closed loop mode, the ambient/battery temperature above 20° F (-7° C) and altitude below 8500 ft.

SET CONDITION
If the PCM multiplies short term compensation by long term adaptive and a purge fuel multiplier and the result is below a certain value for 30 seconds over trips, a freeze frame is stored, the MIL illuminates and a trouble code is stored.

POSSIBLE CAUSES
- Good trip equal to zero
- O2 sensor heater operation
- O2 sensor
- EVAP purge solenoid operation
- O2 signal circuit
- O2 return circuit
- MAP sensor operation
- ECT sensor operation
- Engine mechanical problem
- Fuel filter/pressure regulator
- PCM