DTC P0171 - System Too Lean Bank 1

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DTC DESCRIPTION P0171 - SYSTEM TOO LEAN BANK 1

Description:	This DTC sets when the error in the air to fuel ratio exceeds a calibrated limit.
Possible Causes:	Restricted air filter Biased or damaged mass airflow (MAF) sensor Damaged fuel injector Damaged exhaust gas recirculation (EGR) valve Intake air system or crankcase ventilation system leak Damaged fuel rail pressure sensor Damaged fuel pressure control valve Contaminated or damaged NOx12 sensor
Diagnostic Aids:	This DTC may be accompanied by other DTCs. Diagnose all other DTCs first.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	GO to PINPOINT TEST MX .