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Home >> Buick >> 2004 >> Regal GS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls 3.8L (Introduction, Service & Replacement) >> Repair Instructions >> Heated Oxygen Sensor Replacement - Position 1 >> Removal Procedure
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Removal Procedure

    Fig 1: Locating HO2S Sensor Electrical Connector (3.8L) Components
    GM371512Courtesy of GENERAL MOTORS CORP.
    NOTE: The oxygen sensor may be difficult to remove when the engine temperature is below 48°C (120°F). Excessive force may damage threads in the exhaust manifold or the exhaust pipe.
  1. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement (L36) or Fuel Injector Sight Shield Replacement (L67) in Engine Mechanical 3.8L.
  2. Remove the heated oxygen sensor (HO2S) retaining clip.
  3. Disconnect the HO2S electrical connector (3).
  4. Remove the HO2S electrical connector (4) from the bracket (1).
  5. IMPORTANT: Remove the oxygen sensors with the engine temperature above 48°C (120°F). Otherwise the oxygen sensors may be difficult to remove.
  6. Remove the HO2S (2) from the right exhaust manifold carefully using the J 39194  . See Special Tools and Equipment .