OBDI Knock Sensor Mounting

[khnordeen]

Where do you guys mount the knock sensors on your blocks?

My S50 is in the car and everything, but I can't seem to find pics online or in the Bentley of where the actually sensors are mounted/oriented.

Any photos/help is greatly appreciated. Thanks

-Kyle

[Wishno87]

[scottinAZ]

Wishno has it, there are threaded pads on the block specifically for the sensors.

[khnordeen]

^Thanks a bunch!

[nebulous123]

if they are cracked like wishno's should they be replaced? or does it matter if the exterior plastic is beat up?

[Wishno87]

I left them and the car seems to have been running fine for the last year but I do intend to replace them soon.

[AirplaneBuilder]

Is it a good idea to replace this while the engine is out?? I'm going to be pulling my s50 out of the m3 in a couple weeks. How much are these and how many are there? Never heard of these sensors before ;-)

[Wishno87]

They are somewhat expensive but if you have the money you should change them while the motor is out. Or at least test them to make sure they are within spec.

[Wishno87]

Oh and M50s and S50s have two. OBD2 cars have both built into a single plug.

[nrubenstein]

They should be replaced if they don't look absolutely mint, and you should consider it even if they do. The mint looking set on my 47k mile S50 ended up going bad on me almost immediately, for example.

Note that OBD II knock sensors are very reliable. Jordan/Stuck has been converting them for use on OBD I cars, so it's possible to use the better and cheaper sensors. The downside, though, is that you have to do some wiring adaptation.

[Jonny Cash]

Oh wait, I was told the dual obd2 knock sensors worked with obd1 harness.
Did he share that info on how he made them work with obd1?

[nrubenstein]

Oh wait, I was told the dual obd2 knock sensors worked with obd1 harness.
Did he share that info on how he made them work with obd1?

You need to make an adapter harness or add two plugs, or cut up your engine harness.

[sharky]

get new ones and make sure you align them right and do not over torque or they will crack. I belive its 12-15 ftlb

[Wishno87]

Yes old thread.
Is there a writeup somewhere for converting obd2 knock sensors for obd1?

[Roysneon]

Yes old thread.
Is there a writeup somewhere for converting obd2 knock sensors for obd1?

Interested in this as well.