Installation Procedure

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Installation Procedure
WARNING: This page is about a different car, the 2003 Buick Regal and 2003 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
  1. Install the catalytic converter heat shield.
    Fig 1: Installing Catalytic Converter Heat Shield
    G01969230Courtesy of GENERAL MOTORS CORP.
  2. Install the converter heat shield rivets.
  3. Install the oxygen sensor wiring harness (3) to the catalytic converter heat shield.
    Fig 2: Installing Oxygen Sensor Wiring Harness
    G01969231Courtesy of GENERAL MOTORS CORP.
  4. Install the catalytic converter. Refer to CATALYTIC CONVERTER REPLACEMENT (3.1L)Β  or CATALYTIC CONVERTER REPLACEMENT (3.8L)Β  .
  5. Remove the support from the exhaust system.
  6. Inspect the exhaust system for leaks and underbody contact.
  7. Lower the vehicle.
RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.