im looking for info on part#11 61 1 312 737

its #7 on this chart:
http://bmwfans.info/original/E34/Lim...1/ill-11_1543/


I discovered mine wasnt connected and was rattling around. Amazing it wasnt lost. The ends where the hose was supposed to be connected have no fastening devices. So two questions. Does anyone know what it does? And what way should i reinstall it (two halves, black and white-so which end is the front)?

Thanks for any help