We have four Legacies in our family (95-96). I picked up one recently as a backup car that I can fix up. It has a knock sensor trouble code so I pulled the knock sensor today and discovered it has a different connection than the other cars. A big connection just like our 98 Forester. I had ordered a replacement sensor and was going to put it in today.

So are the connections not Standard? Should I get a knock sensor for a 98 Forester?

there's one sense wire and one ground wire.  splice in the old connector.  ground wire has continuity thru the bolt, sense is the other one.  sometimes there,s only one wire inside, that's the sense wire and it grounds onto the bolt. 

Edited May 11, 20196 yr by nvu

Just cut off the connector and crimp/heat shrink the wires together. The connectors regularly break or are incompatible. You don't need a connector there - you can just unbolt the sensor. It's stupid. 

GD