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Home >> Mercury >> 2008 >> Milan Base, 2.3 Z, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 1182 (Engine Controls - Diagnostic Methods (Except Diesel & Hybrid)) >> Adaptive Fuel Diagnostic Trouble Code (DTC) Diagnostic Techniques >> DTCs P0172/P0175 System Too Rich Diagnostic Aids

DTCs P0172/P0175 System Too Rich Diagnostic Aids

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NOTE: If the system is rich at certain conditions, then the LONGFT PID would be a negative value at that airflow, indicating that decreased fuel is needed.

System rich concerns are caused by fuel system concerns, although the MAF sensor and base engine (for example, engine oil contaminated with fuel) should also be checked.