Oxygen Sensor: Service and Repair

HO2S Service:

CAUTION: The Heated Oxygen Sensors each use a permanently attached pigtail and connector. This pigtail should not be removed from the heated oxygen sensor or catalyst monitor. Damage or removal of the pigtail or connector could affect proper operation of the heated oxygen sensor.

Take care when handling the heated oxygen sensor and catalyst monitor. The in-line electrical connector and louvered end must be kept free of grease, dirt or other contaminants. Also, avoid using cleaning solvents of any type. Do not drop or roughly handle the heated oxygen sensor. A dropped sensor is a bad sensor. The heated oxygen sensor may be difficult to remove when engine temperature is below 48°C (120°F). Excessive force may damage threads in exhaust manifold or exhaust pipe.

REMOVAL PROCEDURE
1. If the HO2S is being replaced, raise the vehicle.
2. Electrical connector.
3. Carefully back out heated oxygen sensor/catalyst monitor.

NOTE: A special anti-seize compound is used on the heated oxygen sensor threads. The compound consists of graphite suspended in fluid 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 a sensor is removed from an engine and if for any reason is to be reinstalled, the threads must have anti-seize compound applied before reinstallation.

INSTALLATION PROCEDURE
1. Coat threads of heated oxygen sensor with anti-seize compound P/N 5613695, or equivalent if necessary.
2. Sensor.

Tighten
Sensor to 41 Nm (30 ft lb).

3. Electrical connector.