Subaru Repair: knock sensor replacement, subaru legacy, knock sensor

Question
I own 99 subaru legacy sus and the engine light comes on and off.  The knock sensor needs replaced.  After researching the part cost of $82 how difficult is it to replace this sensor?  Where exactly is it located?

Answer
On a first generation 2.5l it can be a bit of a challenge to replace the Knock sensor.It will require a twelve mm socket and long extension.Getting the sensor unplugged can be difficult as well.When you go to install the bolt back into the block for the knock sensor wrap the bolt to the socket with a strip of electrical tape to keep the bolt from falling out of the socket.Also be very careful not to cross thread the bolt into the block.