Front Oxygen (A/F) Sensor: Removal

Set the vehicle on a lift.
Disconnect the ground cable from the battery.

Fig 1: Disconnecting Battery Ground Cable
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Disconnect the connector from front oxygen (A/F) sensor.

Fig 2: Identifying Connector From Front Oxygen (A/F) Sensor
Courtesy of SUBARU OF AMERICA, INC.
Disconnect the engine harness fixed by clip (A) from the bracket (B).

Fig 3: Identifying Engine Harness Clip
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Remove the front right side wheel.
Lift up the vehicle.
Remove the service hole cover.

Fig 4: Identifying Service Hole Cover
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Apply spray-type lubricant or equivalent to the threaded portion of front oxygen (A/F) sensor, and leave it for one minute or more.
Remove the front oxygen (A/F) sensor.

CAUTION: When removing the oxygen (A/F) sensor, wait until exhaust pipe cools, otherwise it will damage the exhaust pipe.

Fig 5: Identifying Front Oxygen Sensor

Courtesy of SUBARU OF AMERICA, INC.