replace knock sensor

[Sabres19]

where is the knock sensor located on a 99 legacy can't find a haynes manual and autozone's no help

[blitz]

It's located on top of the crankcase just to the right of the throttle-body (looking into the engine compartment).

 

It's cylindrical in shape, about an inch in diameter, with a single mounting-bolt running down through it's center.

[Legacy777]

knock sensor is the thing with the white connector

 

http://www.main.experiencetherave.com:8080/subaru/images/injectors/DCP_2481.JPG

[hklaine]

http://www.ultimatesubaru.org/forum/showpost.php?p=282768&postcount=4

[JohnVT]

on my 97 OBW, I ended up moving the clutch cylinder and throttle body to reach putting the new one in. Perhaps even that isn't necessary if you use a magnet in a socket with a long extension. It's just hard to see under the intake manifold and several wires running there...

Also, it wasn't obvious to me, but the clip to disconnect the wire connector is on the opposite side of the connector than I was looking! It's easy to remove once you find it! (I don't remember exactly what it looks like, or I would give a better description.)

And, as mentioned in other threads, don't tighten the bolt too much. I think the spec is 16 inch-pounds.

[NorthLight]

I had the check engine light illuminate on my EJ22 96 OBW. Had the OBDII diagnostic tool at my local Schucks tell me that there was something wrong with my knock sensor. Did the diagnostics with a Fluke myself using the shop manual. The manual tells me that I have a bad wiring harness(between the connection to the sensor and the ECM). I'd rather not replace the whole wiring harness. Is there another way of solving this problem? Maybe replacing the sensor, which is easy?

[chef_tim]

http://www.ultimatesubaru.org/forum/showpost.php?p=282768&postcount=4

 

I just used this tread to change mine and it's true, a picture is worth a thousand words. One little clue, make sure the engine is cool before you do it. Space is way to tight to be putting hands into hot spaces:eek: . Later, Tim

[Cougar]

I had the check engine light illuminate on my EJ22 96 OBW. Had the OBDII diagnostic tool at my local Schucks tell me that there was something wrong with my knock sensor. Did the diagnostics with a Fluke myself using the shop manual. The manual tells me that I have a bad wiring harness(between the connection to the sensor and the ECM). I'd rather not replace the whole wiring harness. Is there another way of solving this problem? Maybe replacing the sensor, which is easy?

 

You should be able to check the resistance of the wire by putting the meter probes at each end of the wire with the sensor and ECU connections isolated. If you have more than a couple of ohms resistance then there is something wrong with the wire. I would suspect a bad termination first. You could stick a pin into the wire so you can put your probe on it for a connection to check each end of the wire.

 

If there is a wire break and you can't find the problem you can run a new wire and cut each end of the old wire back enough so you can splice the end connections onto the new wire.

[NorthLight]

If there is a wire break and you can't find the problem you can run a new wire and cut each end of the old wire back enough so you can splice the end connections onto the new wire.

 

Is it difficult to run a new wire through the firewall?

[Cougar]

Is it difficult to run a new wire through the firewall?

 

It's pretty simple. I would use the same path that an existing wire harness uses and run along side of it. Hopefully you can find the problem with the original wire and repair it.