P0172-FUEL SYSTEM 1/1 RICH

For a complete wiring diagram Refer to Section 8W.

When Monitored:
With the engine running in closed loop, the ambient/battery temperature above –7° C (20° F) and altitude below 8500 ft.
Set Condition:
The PCM monitors the Adaptive Memory factor (a combination of Short Term Adaptive and Long Term Adaptive). If the total fuel addition exceeds a calibrated threshold for an extended period, a fuel system lean fault is stored. If the total fuel subtraction exceeds a calibrated threshold, a fuel system rich fault is stored. Two Trip Fault. Three good trips to turn off the MIL

Possible Causes

INTERMITTENT DTC

FUEL DELIVERY SYSTEM

ECT SENSOR, WIRING, OR CONNECTORS

MAP SENSOR, WIRING, OR CONNECTORS

O2 SENSOR, WIRING, OR CONNECTORS

ENGINE MECHANICAL SYSTEM

POWERTRAIN CONTROL MODULE (PCM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

Diagnostic Test

1.DTC IS ACTIVE

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

NOTE: Attempt to operate the vehicle under conditions similar to which the DTC was set.

NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set.

Is the status Active for this DTC?

Yes

Go to 2

Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

2.CHECKING THE FUEL DELIVERY SYSTEM