993 EFI, pipe from distributor

Investigating a rattle when switching engine off, discovered there is a rubber pipe from the body of the distributor which was hanging down and going nowhere. It has a metal clip at end for fastening it to something, but I can't find what it should be connected to. I don't really understand what it's for. Not noticed effect on performance.

Aside from that, Hijet running brilliantly. It is a 1996 Devon camper. Have toured Lake District & Cornwall and never had so much (positive) attention in a vehicle. It has been faultless and I love it!  

Take a photo of this pipe

I think that is just a ventilation pipe.

But don't quote me as I've only had a couple of 993cc engines apart.

But it has a metal clamp at the other end, as if. It attaches to something??

As Matt says its for ventilation and to drain of any condensation that occurs when the engine cools down.

Thanks chaps. That sets my mind at rest!