Oxygen Sensor: Service and Repair

REMOVAL
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Fig.26 O2 Sensor Downstream 2/1 4 Cylinder:

The O(2)S are located in the side 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 O(2)S.

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

4. Remove the O(2)S. Snap-On oxygen sensor wrench (number YA 8875) may be used for removal and installation.

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The engine uses 1 heated oxygen sensors in the 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.25 O2 Sensors 2.7L:

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

INSTALLATION
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The O(2)S are located in the side of the catalytic converter.
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.
2. Install the O(2)S. Tighten to 28 N.m (20 ft. lbs.) torque.
3. Connect the O(2)S wire connector.
4. Lower the vehicle.
5. Install the negative battery cable.

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The engines uses 1 heated oxygen sensors in the 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 N.m (20 ft. lbs.) torque.
2. Connect the heated oxygen sensor electrical connector.
3. Install the negative battery cable.