Chrysler PT Cruiser 2001 Service Manual Supplement page 2551

Symptom:
P0172-1/1 FUEL SYSTEM RICH
When Monitored and Set Condition:
P0172-1/1 FUEL SYSTEM RICH
When Monitored: With the engine running in closed loop mode, the ambient/battery
temperature above -6°C (20°F) and altitude below 8000 ft.
Set Condition: If the PCM multiplies short term compensation by long term adaptive and
the result is below a certain value for two trips, a freeze frame is stored, the MIL
illuminates and a trouble code is stored.
FUEL FILTER/PRESSURE REGULATOR (HIGH)
EVAP SYSTEM FAILURE
INTERMITTENT FUEL SYSTEM DTC
RESTRICTED FUEL SUPPLY LINE
O2 SENSOR SIGNAL CIRCUIT VOLTAGE DROP
O2 SENSOR GROUND CIRCUIT VOLTAGE DROP
O2 SENSOR
TPS VOLTAGE CHANGE NOT SMOOTH
TPS VOLTAGE GREATER THAN 0.92 VOLTS WITH THROTTLE CLOSED
FUEL PUMP INLET STRAINER PLUGGED
FUEL PUMP MODULE
CHECKING ECT SENSOR
ENGINE MECHANICAL PROBLEM
ECT WIRING HARNESS INTERMITTENT
MAP SENSOR (OUT OF CALIBRATION)
TEST
1 Turn the ignition on.
With the DRB, read the DTC's.
Is the Good Trip Counter displayed and equal to zero?
Yes → Go To 2
→ Go To 17
No
POSSIBLE CAUSES
ACTION
91
DRIVEABILITY - GAS
APPLICABILITY
All