E30 Cabby - small round plug under the battery!

[aimlessrock]

folks, I've been doing some welding on the battery tray as i discovered some corrosion under the sound deadening (possibly due to some old spilt bat acid. As i was cleaning the area i noticed a small round plug under the battery tray, with similar ports to the
SI board plug (the pac man plug)..

Any idea what this is?, also can anyone send me the diagram on real oem as all of the plug and fastenings have also been damaged by the acid leak. and after a hour i still can't locate it!

thanks in advance.

cheers

Gary

[PG325]

Sounds like the lambda plug, not used unless you've got a CAT.

[aimlessrock]

Yup it was the O2 plug, have managed to track down the clips etc on real oem and now sorted cheers