Knock Sensor Codes

[nrubenstein]

So, I'm getting codes for both the front and rear knock sensors on the S50.

Would having them hooked up backwards cause a code? (I guessed which plug to use when I hooked them up.)

Is there anything else that I should check before I replace them?

[sharky]

are they cracked? you may have hooked them wrong, if you pull down the covering there is a blue mark on one and a yellow mark on another, they go specifically to front or back. Get the right orientation and torque too.

[nrubenstein]

are they cracked? you may have hooked them wrong, if you pull down the covering there is a blue mark on one and a yellow mark on another, they go specifically to front or back. Get the right orientation and torque too.

Perfect condition, they weren't a problem in the donor car.

I guess I'll have to pull the manifold off and check them.

[mega_t2008]

are they cracked? you may have hooked them wrong, if you pull down the covering there is a blue mark on one and a yellow mark on another, they go specifically to front or back. Get the right orientation and torque too.

[Adrian_Visser]

Hmm so the cracked and beat up looking ones I got along with my other OBD I sensors probably won't work then? I was going to cover them in silicone and see what happened...

[sharky]

I had a hell of a time getting used uncracked OBD1 sensors for my car, I went through atleast 6 or 8. Anyhow I had one good and one with a small crack that I epoxied. It has held fine but If I could do it again I would cough up the 150 or so for 2 new ones.

[nrubenstein]

I had a hell of a time getting used uncracked OBD1 sensors for my car, I went through atleast 6 or 8. Anyhow I had one good and one with a small crack that I epoxied. It has held fine but If I could do it again I would cough up the 150 or so for 2 new ones.

The annoying thing is that the sensors that I have are uncracked and and in great shape. I guess I'll make sure that they are plugged in correctly.

Of course, I also have a DME code now. Second frigging DME, too. If I can just solve the stupid check engine light, I can get this thing registered.

[BustaRhymes325i]

Im hooking mine up right now on my s50, and I cannot differentiate between the 2. I pull back the boot, and they are 2 wires, one is black, one is clear. This is on both connectors. Can anyone verify how to tell which is front and which is rear?

[samiam3356]

Continuity test.

[BustaRhymes325i]

how is this accomplished?

[Adrian_Visser]

With a DMM set to continuity beep. Look up the front and rear knock sensor pins on the DME connector using the ETM.

[FredK]

Look carefully on the harness wiring. The harness I have is actually labeled with 1 and 2 on the wire, right behind the boot.

The wire labeled 1 corresponds to cylinders 1-3. Black wire is continuous with DME Pin 70
The wire labeled 2 corresponds to cylinders 4-6. Black wire is continuous with DME Pin 69

[nrubenstein]

FWIW, the knock sensor code turned out to be a moron problem. I finally gave up and pulled the intake (quite a while ago) and discovered that I had bottomed out the bolt I'd used to install the forward knock sensor.

Still chasing my tail on the DME code, though.