Yippers®

Pour water in the tank and see from where it issues forth.

Eurostile

Mine usually leaks from a hose there, only when it becomes frozen though

customclothiers

It is most likely the headlight washer pump - The one on top - another all too common Audi engineering mistake that will cost you money -
Open the hood - find the washer bottle at the front right of the engine compartment - you can see the washer pump on top - mine leaks due to a crack in the pressure ring that holds the pump in the bottle - I just pushed it back down into the sheath and glued it back in place (a temporary lazy day fix as it will eventually open up again with pressure and heat) - If you have the same exact problem with the plastic pressure ring &amp; don't want to buy a $40 pump you might try a hose clamp wrapped on a piece of rubber hose to keep pressure on the pump so that it doesn't slide up when you put pressure on the system. It should be a recall - everyone has this problem !!!!!<ul><li><a href="http://www.customclothiers.cc">http://www.customclothiers.cc</a</li></ul>