KA24DE Knock Sensor (Detonation) Replacement

The KA24DE knock sensor can be neglected because of two reasons. One being the cost of a replacement sensor. Another is the fact that most people don’t know how to get at the sensor part to replace it. This trick of mine will hopefully help some of you get the job done.

KA24DE Knock Sensor Location

First you have to find the ka24de knock sensor location. It is under the intake manifold, connected to the block by a 12mm bolt. It is located between the second and third intake runners, and is a little larger than a quarter.

Below are pictures of the ka24de knock sensor location with the complete intake manifold removed, and then where to look for the sensor with the intake still attached.

KA24DE Engine Knock Sensor Location

How to Replace KA24DE Knock Sensor

Now how to get at the sensor to replace it. Remove the two 10mm bolts that hold the fuel lines to the upper intake manifold to gain a little more access room.  You also need to remove the oil filter and rear-most intake bracket (three 14mm bolts), as it will be necessary to reach up under the manifold to help guide the new sensor into place.

How to Replace KA24DE Engine Knock Sensor 1
How to Replace KA24DE Engine Knock Sensor 2
How to Replace KA24DE Engine Knock Sensor 3
How to Replace KA24DE Engine Knock Sensor 4

With a LONG (over a foot is best) extension and a 12 mm socket, snake the socket and extension between the 2nd and 3rd intake runners and remove the bolt. If the bolt drops it should be easy to find, especially with the oil filter and bracket off.

How to Replace KA24DE Engine Knock Sensor 5

Next disconnect the knock sensor sub harness from the main engine harness and undo the 12mm bolt and bracket holding the sensor sub harness to the timing chain cover. You will now be able to remove the sensor and sub harness from the KA24DE engine. Disconnect the retaining clip from the sensor, remove the sub harness, and install on the new sensor.

Getting the Knock Sensor Back

Now comes the fun part. Getting the new knock sensor back in.

TRICK ONE: you will need a metal coat hanger (the hook cut off and wire bent straight) or a long part grabber (or wire puller) tool. If using the coat hanger, using some electrical tape, tape the sensor to the coat hanger as close to the sensor as possible (now don’t go crazy with the tape as it will be staying on the harness after installing and you do want to be able to remove the coat hanger right?). If you are using a grabber tool you should just be able to hold the sensor with it.

TRICK TWO: place a good amount of di-electric grease on the sensor bolt and inside the sensor hole. Doing this will keep the bolt from coming out of the KA24DE knock sensor while you are feeding it back into position, even if it’s upside down for a while.

Feed the sensor and sub harness back under the intake manifold and get it in the proximity of where it belongs. (You did remove the oil filter and intake bracket right?) With your long skinny arms reach up under the intake manifold and get the sensor into the right position (the bolt should still be on the sensor). Take your long extension and socket and tighten the new sensor into position with your other hand. 

This may take a few tries but trust me, it will go back in. I don’t have any pictures of this process because I don’t have 3 arms, but it’s going to look like you’re hugging the engine and probing it with the long extension.

Once bolted back to the block, pull out either your grabber tool or coat hanger.  Reattach the sub harness bracket to the timing cover with the 12mm bolt, and plug the sub harness connector back into the main harness. Re-install the intake bracket and a new oil filter (you must re-install the bracket 1st). 

If you were getting the knock (detonation) sensor code (34) from the ECU, clear the code and start the engine. KA24DE knock sensor code 34 should be gone.