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Home >> Subaru >> 2009 >> Outback Limited >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Fuel Injection System (H4SO) >> Front Oxygen (A/F) Sensor >> Installation
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Front Oxygen (A/F) Sensor: Installation

CAUTION: If lubricant is split onto the exhaust pipe, wipe it off with cloth to avoid emission of smoke or causing a fire.
  1. 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 

  2. 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 (A/F) Sensor
    G06334060Courtesy of SUBARU OF AMERICA, INC.
  3. Install the under cover.
  4. Lower the vehicle.
  5. Connect the connector of front oxygen (A/F) sensor connector and fasten the harness with clips.
    Fig 2: Identifying Front Oxygen (A/F) Sensor Connector And Clips
    G06334061Courtesy of SUBARU OF AMERICA, INC.
  6. Connect the ground cable to battery.
    Fig 3: Disconnecting Ground Cable From Battery
    G05019586Courtesy of SUBARU OF AMERICA, INC.