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Front Oxygen (A/F) Sensor: Installation

CAUTION: If the lubricant adheres to the exhaust pipe, wipe it off with cloth to avoid emitting 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)
- LH side
  
  Fig 1: Identifying Front Oxygen (A/F) Sensor (LH Side)
  Courtesy of SUBARU OF AMERICA, INC.
- RH side
  
  Fig 2: Identifying Front Oxygen (A/F) Sensor (RH Side)
  Courtesy of SUBARU OF AMERICA, INC.
Connect the connector of front oxygen (A/F) sensor.
- LH side
  
  Fig 3: Identifying Front Oxygen (A/F) Sensor (LH Side)
  Courtesy of SUBARU OF AMERICA, INC.
- RH side
  
  Fig 4: Identifying Front Oxygen (A/F) Sensor (RH Side)
  Courtesy of SUBARU OF AMERICA, INC.
Lower the vehicle.
Connect the ground cable to battery.