Man if old Absolute Pressure Sensor: Removal

Disconnect the ground cable from battery.

Fig 1: Identifying Battery Ground Cable
Courtesy of SUBARU OF AMERICA, INC.
Disconnect the connector from manifold absolute pressure sensor (A), and remove the filter assembly (B) from intake manifold.
Remove the manifold absolute pressure sensor from the solenoid valve bracket.

Fig 2: Identifying Manifold Absolute Pressure Sensor And Filter Assembly

Courtesy of SUBARU OF AMERICA, INC.