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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 >> Test Description
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Test Description

The numbers below refer to the step numbers in the diagnostic procedures.

  1. 5

    Refer to fuel system diagnostics for a possible fuel condition if conditions were not corrected. See FUEL SYSTEMS in SYSTEM & COMPONENT TESTING - 3.8L BONNEVILLE, GRAND PRIX, IMPALA, LESABRE, MONTE CARLO, PARK AVENUE & REGAL article.
  2. 6

    If conditions were not corrected, a worn cam, worn intake, exhaust values or other engine mechanical failures may be at fault.