Home >> Dodge and Ram >> 2002 >> Ram Van B2500, Van Cargo, 5.9 Z >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0172: 1/1 O2 Sensor Fuel System Rich Or DTC P0175: 2/1 O2 Sensor Fuel System Rich >> Possible Causes