Filler neck connection

Hi,

Quick question, what should be connected to 11 on the diagram below? I'm trying to solve my poor warm starting problem and noticed that nothing is connected to the outlet at the top of my filler neck!

Cheers  

it goes back to the tank so the air inside can come out while your filling it up

Would it cause problems if it was left off?

Yes, I suppose if you filled it up you could possibly have fuel pour all over the place. Also, is the other end exposed, if its not connected properly to the fuel filler neck? And if the fuel system is exposed to the atmosphere, it will evaporate the lighter fractions away (environmental, and fuel going off).

And loads of muck and water will get in to the tank and casue endless running probs

I haven't found the other end yet. Where does it connect to the tank?

Could this lead to a loss of pressure which would in turn explain my warm start problem?

Thanks

Other end is in top corner of tank, difficult to see or get at with tank in situ  :dontknow:  

There as been much debate about whether a GTI tank should be pressurised, mine is.

Some residual pressure may make warm starts easier but should still start without, leaky injectors give similar symtoms :dontknow:

Hmm hopefully the pipe is attached to the tank otherwise it sounds like a tank off job to connect it up.  

It takes ages to start when warm, must be losing pressure. I've checked the injectors (fine), maybe the non-return valve in the pump?

Early-1800 said

Other end is in top corner of tank, difficult to see or get at with tank in situ  :dontknow:  

There as been much debate about whether a GTI tank should be pressurised, mine is.

Some residual pressure may make warm starts easier but should still start without, leaky injectors give similar symtoms :dontknow:

GTI fuel system is held at slight negative pressure during engine running, to prevent escape of fuel vapours. Unless it was completely blocked tight, this has no effect on engine running.

Thanks, so the missing hose explains why I got petrol on my feet when I brimmed the tank the other day but not the warm start problem.

Are there any common culprits besides

Weeping injectors (checked using prowlers test and they are fine)
Faulty non-return valve in fuel pump
Leak between pump and injectors (no smell of fuel but I guess it doesn't take much of a leak)

Cheers