You should have two tanks behind the left headlight, one is your wiper reservoir, the other is an expansion chamber for you fuel tank.
Item 1 below is your fuel expansion chamber. ROW cars vent the expansion chamber at 20 to atmosphere. US emission cars vent the expansion chamber to a charcoal canister in the engine compartment via hose 21.
Your broken line should be 9mm ID, 14mm OD. (#'s 6,7,8,9). Pretty sure your broken hose is #6, Porsche P/N N 020 359 1
or 4mm ID, 7mm OD (#16,17,21)
You might need to remove your wiper res to get to the expansion chamber which is a PITA.
