P0172

Tests 237 - 241:

Tests 242 - 244:

Tests 245 - 248:

Tests 249 - 250:

SYMPTOM
P0171 - 1/1 FUEL SYSTEM RICH

WHEN MONITORED
With the engine running in closed loop mode, the ambient/battery temperature above 20 °F and altitude below 8000 ft.

SET CONDITION
If the PCM multiplies short term compensation by long term adaptive and a certain percentage is exceeded for two trips, a freeze frame is stored, the MIL illuminates and a trouble code is stored.

POSSIBLE CAUSES
- Fuel pump module defective
- TPS voltage change not smooth
- TPS Voltage < 0.92 volts
- Fuel inlet strainer plugged
- ECT sensor defective (out of calibration)
- MAP sensor defective (out of calibration)
- Engine mechanical problem
- Fuel filter/pressure regulator defective (high)
- Fuel filter/pressure regulator defective (low)