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Home >> Chevrolet >> 2003 >> Impala LS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Self-Diagnostics - 3.8L >> Diagnostic Tests >> DTC P0171: Fuel Trim System Lean >> Diagnostic Procedures
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Diagnostic Procedures

NOTE: If any DTCs are set, other than P0171, diagnose those DTCs before continuing. See DIAGNOSTIC TROUBLE CODE DEFINITIONS .
Fig 1: DTC P0171: Fuel Trim System Lean (Steps 1-5)
G00250367Courtesy of GENERAL MOTORS CORP.
Fig 2: DTC P0171: Fuel Trim System Lean (Steps 6-8)
G00250368Courtesy of GENERAL MOTORS CORP.
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