For 1990-2009 cars

### Removal Procedure

Notice: The O2S-1 uses a permanently attached pigtail and connector. This pigtail should not be removed from the O2S-1. Damage or removal of the pigtail or connector could affect proper operation of the O2S-1.

1. Turn the ignition OFF.
2. Disconnect the O2S-1 harness connector.
3. Use a liquid penetrate before removing the sensor.

Important: Do not allow penetrating oils to contact the upper, air reference, portion of the sensor. This is the area between the hex and lead wires.

Caution: Removal of the sensor is easier if the exhaust system is warmed up slightly. Be careful that it is not too hot to work on safely. Applying penetrating oil to the threads while moving the sensor back and forth will also aid in removal and will decrease the chance of exhaust pipe thread damage.

4. Remove the O2S-1.

### Installation Procedure

1. Apply anti-seize compound Saturn P/N 21485279 (or equivalent) to the threads of the O2S-1.

Notice: Silicone products will damage the O2S-1. Use only nickel based anti-seize compound that does not contain silicone.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

2. Install the O2S-1 in the exhaust manifold.

Tighten
Tighten the oxygen sensor to 45 N·m (33 lb ft).

Important: The attached pigtail and connector and the louvered end must be kept free of dirt, grease or other contaminants. Avoid using cleaning solvents of any type.

3. Connect the O2S-1 harness connector. Push in the connector until a click is heard and pull back to confirm a positive engagement.