Diagnostic Procedures

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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)

Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC P0171: Fuel Trim System Lean (Steps 6-8)

Courtesy of GENERAL MOTORS CORP.