2003 Subaru Forester XS, AutomaticFACTORY OEM SERVICE PROCEDURE

Knock Sensor: Removal

  1. Disconnect the ground cable from battery.
    Fig 1: Disconnecting Ground Cable From Battery
    G02945220Courtesy of SUBARU OF AMERICA, INC.
  2. Remove the air cleaner case. Refer to REMOVAL , Air Cleaner Case.
  3. Disconnect the knock sensor connector.
    Fig 2: Identifying Knock Sensor Connector For Removal
    G02945221Courtesy of SUBARU OF AMERICA, INC.
  4. Remove the knock sensor from the cylinder block.
    Fig 3: Removing Knock From Cylinder Block
    G02945222Courtesy of SUBARU OF AMERICA, INC.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.