Front Oxygen (A/F) Sensor: Installation

CAUTION: If lubricant is spilt over the exhaust pipe, wipe it off with cloth to avoid emission of smoke or causing a fire.

Before installing front oxygen (A/F) sensor, apply anti-seize compound only to the threaded portion of front oxygen (A/F) sensor to make the next removal easier.
CAUTION: Never apply anti-seize compound to the protector of front oxygen (A/F) sensor.

Anti-seize compound:

NEVER-SEEZ NSN, JET LUBE SS-30 or equivalent
Install the front oxygen (A/F) sensor.
Tightening torque:

21 N.m (2.1 kgf-m, 15.5 ft-lb)

Fig 1: Identifying Front Oxygen Sensor RH And LH
Courtesy of SUBARU OF AMERICA, INC.
Install the catalytic converter lower cover. (U5 model)
Tightening torque:

13 N.m (1.3 kgf-m, 9.6 ft-lb)

Fig 2: Locating Catalytic Converter Lower Cover Screws
Courtesy of SUBARU OF AMERICA, INC.
Connect the connector (A) of front oxygen (A/F) sensor.

Fig 3: Identifying Front Oxygen (A/F) Sensor Connector
Courtesy of SUBARU OF AMERICA, INC.
Lower the vehicle.
Connect the ground cable to battery.