Non-Turbo Model

Disconnect the ground cable from battery.

Fig 1: Disconnecting Ground Cable From Battery
Courtesy of SUBARU OF AMERICA, INC.
Disconnect the connector (A) from the mass air flow and intake air temperature sensor, and remove the clip (B).

Fig 2: Mass Air Flow And Intake Air Temperature Sensor Connector And Clip
Courtesy of SUBARU OF AMERICA, INC.
Loosen the clamp (A) which connects the air cleaner case to intake boot.
Remove the clips (B) securing the upper side of the air cleaner case.

Fig 3: Air Cleaner Case Clips And Clamp
Courtesy of SUBARU OF AMERICA, INC.
Remove the air cleaner case (rear) and air cleaner element.

Fig 4: Removing Air Cleaner Case (Rear) And Air Cleaner Element
Courtesy of SUBARU OF AMERICA, INC.
Install in the reverse order of removal.
CAUTION: Be sure to use SUBARU genuine air cleaner element depending on the engine type when replacing the air cleaner elements. Using other air cleaner element may affect the engine performance.
NOTE:
- Check that there are no foreign objects in the air cleaner case.
- When installing the air cleaner case (rear), align the protrusion of the air cleaner case (rear) to the hole on the air cleaner case (front) to install.
  
  Fig 5: Aligning Protrusion Of Air Cleaner Case (Rear) To Hole On Air Cleaner Case (Front)
  Courtesy of SUBARU OF AMERICA, INC.
Tightening torque:

Clamp (A)

3 N.m (0.3 kgf-m, 2.2 ft-lb)

Fig 6: Air Cleaner Case Clips And Clamp
Courtesy of SUBARU OF AMERICA, INC.