LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Subaru >> 2021 >> WRX STI >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Fuel Injection System (2.5L) >> Rear Oxygen Sensor >> Removal
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Rear Oxygen Sensor: Removal

  1. Disconnect the ground cable from battery.
  2. Lift up the vehicle.
  3. Remove the transmission under cover.
  4. Disconnect the connector from the rear oxygen sensor, and remove the clip (A) holding the rear oxygen sensor harness.
    G08538822Courtesy of SUBARU OF AMERICA, INC.
  5. Apply spray-type lubricant (004301003) to the threaded portion of rear oxygen sensor, and leave it for one minute or more.
  6. Remove the rear oxygen sensor.
    CAUTION: When removing the rear oxygen sensor, wait until exhaust pipe cools, otherwise it will damage the exhaust pipe.
    G08538823Courtesy of SUBARU OF AMERICA, INC.