Oxygen Sensor: Service and Repair

Heated Oxygen Sensor (HO2S)
REMOVAL
1. Disconnect the negative battery cable.

2. Locate the four oxygen sensors.




- Bank 1 sensor 1 is mounted on the exhaust pipe ahead of the right-hand catalytic converter.




- Bank 1 sensor 2 is mounted behind the right-hand catalytic converter.




- Bank 2 sensor 1 is mounted on the exhaust pipe ahead of the left-hand catalytic converter.




- Bank 2 sensor 2 is mounted behind the left-hand catalytic converter.

3. Disconnect the pigtail from the wiring harness.

IMPORTANT: The pigtail is permanently attached to the sensor. Be careful not to pull the wires out.

NOTE: Do not use a torch to remove an HO2S unless the sensor is being replaced. Using a torch could damage the sensor.

4. Remove the sensor from the exhaust pipe.




- Because of the expansion and contraction of the metal in the exhaust system over time, this may be difficult if the engine temperature is below 48 °C (120 °F).

INSTALLATION

IMPORTANT:
- A special anti-seize compound, P/N 5613695, is used on the HO2S threads. This compound consists of glass beads suspended in a liquid graphite solution. The graphite burns away with engine heat, 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 and is to be reinstalled for any reason, the threads must have anti-seize compound applied.
1. Apply anti-seize compound or the equivalent to the threads of the oxygen sensor, if necessary.
2. Install the oxygen sensor on the exhaust pipe in its original position.




Tighten:
3. Connect the pigtail to the wiring harness.
4. Connect the negative battery cable.