GM 12597989
Oxygen Sensor

In order to replace the Heated Oxygen Sensor (HO2S) for Bank 1 Sensor 2, treat the oxygen sensors with care to avoid loss of function, making sure not to leave the electrical connector and exhaust inlet uncontaminated with any solvents and do not drop the sensor. Use a cool engine to help remove heated oxygen sensors more easily. Remove heated oxygen sensors with the use of the engine when the temperature is above 48°C (120°F). Dismantle the oxygen sensor wiring harness heat shield first. Pull the engine harness electrical connector off the HO2S and then remove the sensor. When installing, the use of a special anti-seize compound on the HO2S threads, consisting of liquid graphite and glass beads (not to be confused with tape); New or service replacement sensors have this compound pre-applied on them. If reusing the old HO2S use anti-seize, GM P/N 12377953 or equivalent on threads. Install the HO2S and tighten it with the torque of 41 Nm (30 lb ft). Connect the engine harness electrical connector to the HO2S and restore the oxygen sensor wiring harness heat shield.

Remove the oxygen sensor electrical connector from the ignition coil bracket and take out the HO2S from the exhaust manifold.

Apply anti-seize compound P/N 12377953.

Remove the intake manifold cover.

Carefully remove the HO2S using the Oxygen Sensor Wrench (J 39194), ensuring the engine temperature is above 48°C (120°F).

The HO2S should be removed when the engine temperature is above 48°C (120°F) to avoid difficulty during removal.

The engine temperature should be above 48 °C (120°F) to facilitate easier removal.

Coat the threads with anti-seize compound, GM P/N 12377953 or equivalent, before installation.

GM P/N 12377953 or equivalent.

Disconnect the engine harness electrical connector from the HO2S and then remove the sensor.

Tighten the HO2S to 41 Nm (30 lb ft).