LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Buick >> 2009 >> Allure CXL >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System & Fuel System - 3.8L - Introduction >> Repair Instructions >> Heated Oxygen Sensor 1 Replacement >> Removal Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Removal Procedure

    Fig 1: HO2S Electrical Connector & Right Exhaust Manifold
    GM911055Courtesy of GENERAL MOTORS CORP.
    CAUTION: The Heated Oxygen Sensor (HO2S) and the Oxygen Sensor use a permanently attached pigtail and connector. Do not remove this pigtail from the Heated Oxygen Sensor. Damage or the removal of the pigtail or the connector could affect the proper operation of the sensor.
    Take care when handling the HO2S and the O2S. Keep the in-line electrical connector and the louvered end free of grease, dirt, or other contaminants. Also avoid using cleaning solvents of any type. Do not drop the HO2S or the O2S. Do not roughly handle the HO2S or the O2S.
    CAUTION: 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 .
  2. Remove the heated oxygen sensor (HO2S) retaining clip.
  3. Disconnect the HO2S electrical connector (1).
  4. Remove the HO2S electrical connector (1) from the fuel injector sight shield bracket.
  5. NOTE: Remove the oxygen sensors with the engine temperature above 48°C (120°F). Otherwise the oxygen sensors may be difficult to remove.
  6. Use the J 39194  to remove the HO2S (2) from the right exhaust manifold. See Special Tools .