Hi, 

My sunroof is leaking along the back edge when it is parked on a slant facing forwards, downhill. The drain plugs are clear. It's almost as if the back doesn't even have a chance to flow into the drains when it's on a slight slant. The seal doesn't seem to seal completely as i can just about see a gap to the pull back interior sunshade bit. Any ideas on what I could do to fix this as it pours in quite heavily! Do I need a new seal. Or to adjust the sunroof? I did notice a plastic or age clip loose in the sunroof gutters when it was open.. I have since misplaced said clip! But couldn't see where it went! 

Try this. I know it’s from a Passat forum, but they use the same sunroof mech etc. 

https://www.passatworld.com/forums/volkswagen-passat-b5-discussion/315456-how-resetting-sunroof-0-position.html#/topics/315456?page=1