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Home >> Jeep >> 2007 >> Commander Overland, RWD >> Repair and Diagnosis >> Engine Performance >> System >> DTCS P0123 To P0174 >> P0171-Fuel System 1/1 Lean >> Possible Causes
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Possible Causes

Possible Causes 
RESTRICTED FUEL SUPPLY LINE
FUEL PUMP INLET STRAINER PLUGGED
FUEL PUMP MODULE
O2 SIGNAL CIRCUIT
O2 RETURN CIRCUIT
O2 SENSOR
MAP SENSOR
ECT SENSOR
ENGINE MECHANICAL
FUEL FILTER/PRESSURE REGULATOR
POWERTRAIN CONTROL MODULE (PCM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .