Heated Oxygen Sensor (HO2S) Replacement (Pre-Catalyst)

HEATED OXYGEN SENSOR (HO2S) REPLACEMENT (PRE-CATALYST)

REMOVAL PROCEDURE




1. Remove the exhaust manifold heat shield.

NOTE:
- The oxygen sensor uses a permanently attached pigtail and connector. Do not remove the pigtail from the oxygen sensor. Damage to or removal of the pigtail connector could affect proper operation of the oxygen sensor.
- The use of excessive force may damage the threads in the exhaust manifold/pipe.
- Refer to Heated Oxygen Sensor (HO2S) Resistance Learn Reset Notice in Service Precautions.

IMPORTANT:
- The in-line connector and louvered end must be kept clear of grease, dirt or other contaminants. Avoid using cleaning solvents of any type. DO NOT drop or roughly handle the oxygen sensor (O2S).
- The O2S may be difficult to remove when the engine temperature is less than 48°C (120°F).




2. Disconnect the O2S harness connector.
3. Remove the O2S.

INSTALLATION PROCEDURE

1. Coat the threads of the O2S with anti-seize compound, if necessary.

IMPORTANT: A special anti-seize compound is used on the O2S threads. The compound consists of a liquid graphite and glass beads. The graphite will burn away, but the glass beads will remain, making the sensor easier to remove. New or service sensors will have the compound applied to the threads. If a sensor is removed and is to be reinstalled, the threads must have an anti-seize compound applied before installation.




2. Install the O2S.

NOTE: Refer to Fastener Notice in Service Precautions.

Tighten the O2S to 30 N.m (22 lb ft).

3. Connect the O2S harness connector.




4. Install the exhaust manifold heat shield.