LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Chevrolet >> 2003 >> Impala LS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Troubleshooting - No Codes - 3.8L >> Symptoms >> Engine Backfires >> Additional Checks
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Additional Checks

  1. Inspect Intake and exhaust manifolds for casting flash.
  2. Check Torque Converter Clutch (TCC) operation. See appropriate DIAGNOSIS article in TRANSMISSIONS.
  3. Check exhaust system for possible restrictions. Inspect for the following:
    • Inspect exhaust system for damaged or collapsed pipes.
    • Inspect mufflers for heat distress or possible internal failure.
    • For possible plugged 3-way catalytic converter. See EXHAUST SYSTEM CHECK under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING - 3.8L BONNEVILLE, GRAND PRIX, IMPALA, LESABRE, MONTE CARLO, PARK AVENUE & REGAL article.