Upstream Oxygen Sensor Replacement

Fig 121 Upstream Heated Oxygen Sensor:

The upstream oxygen sensor is installed in the exhaust manifold (Fig. 121).

CAUTION: Do not pull on the oxygen sensor wire when unplugging the electrical connector.

WARNING: The exhaust manifold and catalytic converter may be extremely hot. Use care when servicing the oxygen sensor.

REMOVAL
1. Raise and support vehicle.
2. Unplug oxygen sensor electrical connector.
3. Use a socket such as Snap-On YA8875 or equivalent to remove sensor.
4. When the sensor is removed, the exhaust manifold threads must be cleaned with an 18 mm X 1.5 + 6E tap. If using original sensor, coat the threads with Loctite 771-64 anti-seize compound or equivalent.

INSTALLATION
1. Reverse removal procedure to install a new sensor.
- New sensors are packaged with compound on the threads and no additional compound is required.
- The sensor must be tightened to 27 Nm (20 ft lb) torque.