Chrysler Repair: what is causing the reading SYSTEM TOO RICH, sensor operation, sensor sweep


Question
Hi my chrysler is a 300m the year is 2000. It's been about a month that my check engine light comes on steady as soon as I turn my car. I had it diagnosed and result code is PO172. Any suggestions whats the cause and how to repair it.

Answer
Symptom List:
P0172-1/1 FUEL SYSTEM RICH
P0175-2/1 FUEL SYSTEM RICH
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be 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 20 deg. 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.
P0175-2/1 FUEL SYSTEM RICH
When Monitored: With the engine running in closed loop mode, the ambient/battery
temperature above 20 deg. 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.
POSSIBLE CAUSES
INTERMITTENT CONDITION
RESTRICTED FUEL SUPPLY LINE
FUEL PUMP INLET STRAINER PLUGGED
FUEL PUMP MODULE
O2 SENSOR HEATER OPERATION
O2 SENSOR
EVAP SYSTEM OPERATION
O2 SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE
O2 SENSOR SIGNAL CIRCUIT OPEN
TPS VOLTAGE GREATER THAN 0.92 VOLTS WITH THROTTLE CLOSED
TP SENSOR SWEEP
MAP SENSOR OPERATION
ECT SENSOR OPERATION
ENGINE MECHANICAL PROBLEM
FUEL FILTER/PRESSURE REGULATOR (HIGH)
PCM
104