Impreza F4-2.5L (2008)
Oxygen Sensor: Service and Repair
Rear Oxygen Sensor
Rear Oxygen Sensor
REMOVAL
1. Set the vehicle on a lift.
2. Disconnect the ground cable from the battery.
3. Remove the air intake duct.
4. Remove the clip fastening the harness and disconnect the rear oxygen (A/F) sensor connector.
5. Lift up the vehicle.
6. Remove the under cover.
7. Apply spray-type lubricant to the threaded portion of rear oxygen sensor, and leave it for one minute or more.
8. Remove the rear oxygen sensor.
CAUTION: When removing the rear oxygen sensor, wait until exhaust pipe cools, otherwise it will damage the exhaust pipe.
INSTALLATION
1. Before installing rear oxygen sensor, apply the anti-seize compound only to the threaded portion of rear oxygen sensor to make the next removal
easier.
CAUTION: Never apply anti-seize compound to the protector of rear oxygen sensor.
Anti-seize compound: NEVER-SEEZ NSN, JET LUBE SS-30 or equivalent