Faulty Lambda sensor - location?

[steamship]

Both the V12 and W12 are 'split' into 4 banks. Banks 1 and 2 are on the left side of the engine, as you look at it from the front of the car. Banks 3 and 4 are the right side. There are two lambda sensors per bank, labelled 1 and 2. 1 is the pre-cat, and 2 is the post-cat.

With that in mind, B3S1 'should' be sensor G285 (top left) in the attached image. The image is taken from the following SSP on the W12 engine:

SSP490 6.3l W12 FSI engine.pdf

If I was replacing it, I'd first disconnect G286, and go for a very short drive, and then scan the car again. If my numbering is correct, you'd then get an error code for B4S1 (G286). If that was the case, I'd then reconnect it, and replace G285.

[Horrgakx]

Cracking, thanks very much!!

That looks like it might be a challenge to change....?

[steamship]

Originally Posted by Horrgakx

That looks like it might be a challenge to change....?

I think that applies to most things on the W12.

[Horrgakx]

I still haven't bought the replacement yet, mainly because I'm unsure of the part number, though I think it could be;
- 07P906265D (Cylinder 1,3,5) (Black) In front of catalyst
- 07P906265E (Cylinder 2,4,6) (Green) In front of catalyst
- 07P906265H (Cylinder 7,9,11) (Grey) In front of catalyst
- 07P906265J (Cylinder 8,10,12) (Brown) In front of catalyst

The plug has a length of wire attached, so it won't be as simple as say, a spark plug, where I could just pull the top connector away. So if that's the case I have no idea where it goes and plugs in to.


Thanks.