Replacing 3-4 Knock Sensor on M42

[cslayman]

Hi,
I need to replace the cylinder 3-4 knock sensor on my '95 M42 ti. It's buried pretty deep under the lower manifold. Is there a way to replace it without removing the lower manifold?

Thanks,
Charlie

[ClubSport]

How do you know the sensor is bad? What are the symptoms?

[Danny318]

there really isnt a way to get to it without taking the manifold off. I mean I wished the same thing, but look, you cant even see it.

[Danny318]

[cslayman]

I'm getting the fault code from Peak RX5 that corresponds to knock sensor 3-4. I cleared it and it has come back again.

[cslayman]

Danny,
That's what I was afraid of. (I assume your M44 knock sensor locations are the same as my M42 - even though the parts are slightly different). Just wondering if anyone had a trick to get at it from underneath.

Thanks,
Charlie

[Danny318]

Thats a pic I found on here but it looks just like my car, I had the engine on a stand and there appear to be no trick. If you can get under it and perhaps fish a nice ratcheting spanner wrench up there you might, but I doubt it.

[xxxJohnBoyxxx]

I'm pretty sure there is no way to do this correctly without removing the intake and water pipe. You want to clean the knock sensor block surface and use a torque wrench to torq them correctly or the new sensors can error too. When they error they cut timing back to minimal advance. Sorry for the bad news. M44 and M42 blocks have the same location for the sensors

[Danny318]

you are still perfectly safe to drive with it the way it is though. Just wait till you're feeling motivated and tear the bitch apart.

[fieldhb]

My Check Engine light came on, so I bought the fault code reader / reset tool from Bavarian.
So the code came back table 07 code d3 - knock sensor cyl 3-4.
I looked in the bentleys, probably like you did. Take Manifold off and all.
So I called the mechanic that works on my car in Columbus, and he told me to reset it and drive it again.
So i will reset it first and see how it goes.

[fieldhb]

So I go to reset the engine light, and the instructions say that it will return to display "Fc" when it is done. But I wait like 2 minutes and it stays on "--".
So I unplug it and start engine and the check engine light is off.
Anyone else have the display not match the instructions ?