DTC P0172: System Too Rich (Bank 1)

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P0172 - SYSTEM TOO RICH (BANK 1)

Description:	The adaptive fuel strategy continuously monitors the fuel delivery hardware. The test fails when the adaptive fuel tables reach a lean calibrated limit. Refer to POWERTRAIN CONTROL SOFTWARE , FUEL TRIM for additional information.
Possible Causes:	Fuel System: Leaking fuel injectors Fuel return line restricted Fuel rail pressure (FRP) sensor bias EVAP canister purge valve is leaking when the canister is full Base Engine: Engine oil contamination Intake Air System: Damaged or contaminated mass airflow (MAF) sensor
Diagnostic Aids:	View the freeze frame data to determine the operating conditions when the DTC was set. Observe the LONGFT1 and LONGFT2 PIDs. Refer to ADAPTIVE FUEL DIAGNOSTIC TROUBLE CODE (DTC) DIAGNOSTIC TECHNIQUES , for additional information and the appropriate pinpoint test for specific concern identification.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	GO to PINPOINT TEST H .