Sensor, Oxygen: Installation: Notes

CAUTION:

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

The engine is equipped with four heated oxygen sensors:

The right upstream oxygen sensor is referred to as the 1/1 sensor.
The right downstream oxygen sensor is referred to as the 1/2 sensor.
The left upstream oxygen sensor is referred to as the 2/1 sensor.
The left downstream oxygen sensor is referred to as the 2/2 sensor.