Oxygen Sensor: Service and Repair

INSTALLATION

NOTE: The engine is equipped with two heated oxygen sensors:

- The upstream oxygen sensor (1) is referred to as the 1/1 sensor.
- The downstream oxygen sensor (2) is referred to as the 1/2 sensor.






1. If reinstalling the original oxygen sensor, coat the sensor threads with an anti-seize compound such as Loctite 771- 64 or equivalent. New sensors have compound on the threads and do not require an additional coating. Do Not add any additional anti-seize compound to the threads of a new oxygen sensor.
2. Install the downstream oxygen sensor and tighten to 45 Nm (33 ft. lbs.).
3. Engage the downstream oxygen sensor wire harness to the retainers (2).
4. Lower the vehicle.





5. Install the upstream stream oxygen sensor and tighten to 45 Nm (33 ft. lbs.).

CAUTION:
Never apply any type of grease to the oxygen sensor electrical connector, or attempt any repair of the sensor wiring harness.





6. If installing the downstream oxygen sensor, connect the heated oxygen sensor wire harness connector (2).
7. If installing the upstream oxygen sensor, connect the heated oxygen sensor wire harness connector (1).
8. Engage the oxygen sensor wire harness from retainers (3).
9. Connect the negative battery cable and tighten nut to 5 Nm (45 in. lbs.).
10. The Oxygen Sensor Relearn procedure must be performed using the scan tool following replacement of any oxygen sensor.