Oxygen Sensor: Service and Repair

REMOVAL
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The engines uses two heated oxygen sensors, one in each exhaust manifold.

CAUTION: When disconnecting the sensor electrical connector, do not pull directly on wire going into sensor.

1. Remove the negative battery cable.
2. Disconnect the heated oxygen sensor electrical connector.

Fig.21 Upstream Heated Oxygen Sensor 1/1:

3. Use a socket such as Snap-On YA8875 or a crow foot wrench to remove oxygen sensor.

Fig.22 Downstream Heated Oxygen Sensor 1/2:

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The O2 sensors are located at the outlet ends of the catalytic converter.

WARNING: THE EXHAUST MANIFOLD, EXHAUST PIPES AND CATALYTIC CONVERTER BECOME VERY HOT DURING ENGINE OPERATION. ALLOW ENGINE TO COOL BEFORE REMOVING OXYGEN SENSOR.

1. Remove the negative battery cable.
2. Raise and support the vehicle.
3. Disconnect the wire connector from the O2 sensors.

CAUTION: When disconnecting the sensor electrical connector, do not pull directly on wire going into sensor.

4. Remove the O2 sensors. Snap-On oxygen sensor wrench (number YA 8875) may be used for removal and installation.

INSTALLATION
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The engines uses two heated oxygen sensors, one in each exhaust manifold.
1. After removing the sensor, the exhaust manifold threads must be cleaned with an 18 mm X 1.5 + 6E tap. If reusing the original 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. Tighten the sensor to 28 Nm (20 ft. lbs.) torque.
2. Connect the heated oxygen sensor electrical connector.
3. Install the negative battery cable.

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The O2 sensor are located at the outlet ends of the catalytic converter.

Threads of new oxygen sensors are factory coated with anti-seize compound to aid in removal. DO NOT add any additional anti-seize compound to the threads of a new oxygen sensor.
1. Install the O2 sensor. Tighten to 28 Nm (20 ft. lbs.) torque.
2. Connect the O2 sensor wire connector.
3. Lower the vehicle.
4. Install the negative battery cable.