[Vwdiesel] black tube by coolant bottle what is it for??

[Stpndsmnn at aol.com]

Hi,

I haven't really ever posted before but I had a question,  I have an 81 diesel Jetta 1.6 NA.  there is a black tube thing on the drivers side by the coolant bottle, it has a vacuum line to it and I think a wire that runs someplace.  Basically I was just wondering what it is for and where that single wire goes that comes out of the end of it??

Thanks for any help
Matt Kramer

81 1.6 Jetta
turbo conversion in progress
with K26 turbo and modified Audi manifold