Catalyst Monitor (HO2S) Oxygen Sensors

Removal Procedure

Notice: The HO2S 2 uses a permanently attached pigtail and connector. This pigtail should not be removed from the rear heated oxygen sensor. Damage or removal of the pigtail or connector could affect proper operation of the rear heated oxygen sensor.

Important: Take care when handling the Rear Heated Oxygen Sensor 2 (HO2S 2). The in-line electrical connector and louvered end like the O2S 1 must be kept free of grease, dirt or other contaminants. Avoid using cleaning solvents of any type. DO NOT drop or roughly handle the HO2S 2.

1. Turn the ignition switch OFF.

2. Disconnect the HO2S 2 electrical connector.

Notice: Excessive force may damage the threads in the exhaust pipe.

3. Carefully remove the rear heated oxygen sensor 2.


Installation Procedure

Important: A special anti-seize compound is used on the HO2S 2 sensor threads. The compound consists of a liquid graphite and glass beads. The graphite will burn away, but the glass beads will remain, making the sensor easier to remove. New or service sensors will already have the compound applied to the threads. If the sensor is removed from the exhaust, and if for any reason it is to be reinstalled, the threads must have an anti-seize compound applied before reinstallation.

1. Coat the threads of the HO2S 2 with anti-seize compound, if necessary.

2. Install the HO2S 2. Tighten the HO2S 2 to 41 Nm (30 lb. ft.).

3. Connect the HO2S 2 electrical connector.