Hi, I've had a problem with my Tiguan leaking into the front passenger well for over 3 years. Took it to VW who said the drain holes were blocked, so they unblocked them, by sticking a length of net curtain wire down them. This seemed to work for a while but, yes it came back again...I paid £240 for VW to check where the leak was to no avail. They had a hose on it, recyclable water, for two hours and no leak found. To cut a long story short it kept on happening even after I'd cleaned out the drain holes (4 one at each corner of the sunroof). It got desperate the other day, it had been raining off and on for 4 days and when I checked the footwell had about 2 gallons of water in it. I lifted the carpet and removed a rubber bung in the floor which got rid of the standing water but the foam underlay and mats were ringing wet. I used my VAX to remove as much as possible from the carpets. The end result is I found a video on YouTube, I'd looked many times before and not found this. It appears that , and no VW technician seemed to know this, the ends of the drain tubes have little valves which are supposed to open when the weight of water in the tubes reaches a certain limit.
These valves do not open correctly and therefore even after a clean of the drains a small amount of rain fills up the tube quite quickly and the water overflows over the seals in the sunroof, down the pillar and into the footwell. I've put a link to the YouTube video below. Basically you remove these 'spider catchers', they are just small round orange disks at the bottom of the pipes, it took me about 10 mins,. I've now tested mine over 3 very wet days and not a drop of water has come into the footwell, I even poured water in myself and it just drains away.....result.
VW Tiguan R-Line (Wet Carpets?) Spider Trap valves removal. Pano-Roof. - YouTube
These valves do not open correctly and therefore even after a clean of the drains a small amount of rain fills up the tube quite quickly and the water overflows over the seals in the sunroof, down the pillar and into the footwell. I've put a link to the YouTube video below. Basically you remove these 'spider catchers', they are just small round orange disks at the bottom of the pipes, it took me about 10 mins,. I've now tested mine over 3 very wet days and not a drop of water has come into the footwell, I even poured water in myself and it just drains away.....result.
VW Tiguan R-Line (Wet Carpets?) Spider Trap valves removal. Pano-Roof. - YouTube