How do you replace a knock sensor on a 1997 subaru legacy?

The knock sensor is located on the top of the block. It is best seen looking down from the drivers side just to the left of the intake manifold intake. If you have a manual trans it is much easier to replace by unbolting the clutch slave cylinder. A long extension will remove the single bolt that goes through the sensor.

Note the orientation of the sensor. It installs at a 45 degree angle from the centerline.

The wire can be removed by needle nose pliers and a screwdriver for force.

To reinstall tape the bolt to the socket and lower into place.