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Home >> Subaru >> 2021 >> WRX Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Fuel Injection System (2.0L) >> Front Oxygen (A/F) Sensor >> Removal
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Front Oxygen (A/F) Sensor: Removal

  1. Disconnect the ground terminal from battery sensor. Refer to NOTE>NOTE>BATTERY .
  2. Remove the radiator main fan & fan motor assembly. Refer to COOLING(W/O STI)>RADIATOR MAIN FAN AND FAN MOTOR>REMOVAL .
  3. Lift up the vehicle.
  4. Remove the under cover. Refer to EXTERIOR/INTERIOR TRIM>FRONT UNDER COVER>REMOVAL .
  5. Disconnect the connector (A) on the front oxygen (A/F) sensor from the engine wiring harness, and remove the clip (B) which secures the front oxygen (A/F) sensor harness to the water pump cover.
  6. Apply spray-type lubricant (004301003) to the threaded portion of front oxygen (A/F) sensor, and leave it for one minute or more.
  7. Remove the front oxygen (A/F) sensor.
    CAUTION: When removing the front oxygen (A/F) sensor, wait until exhaust pipe cools, otherwise it will damage the exhaust pipe.
    G10266244Courtesy of SUBARU OF AMERICA, INC.
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