Morning
5 hours of heavy rain overnight, and having stripped the taped up roof rail last night, I was very happy to still see a dry headlining. No water ingress at all. Looks like the sunroof leak is the culprit - only on the drivers side and in the area of the hinge for the wind deflector (see photo below).
Thanks for the video link, Boots. I hadn’t seen that but the way he tested the roof is pretty much what I did, and posters on other Audi forums have also identified this point. Seems as though the seal between the metal and plastic parts of the sunroof frame deteriorates with age and breaks down allowing some water to seep in. With the freeze and thaw winter conditions, the leaking frame gets worse. Some have tried to fix this with a liquid polymer sealant called Captain Tolleys (used extensively by boat owners). But you need to wait for warmer weather before going down that route. Others have had the entire sunroof replaced at a fabulous cost (£2-3,000). The third option is to have the roof frame rebuilt at about a third of the cost of a new one. I have found only one company with a track record of doing this successfully (Surrey Sunroofs, between Guildford and Gatwick).
I plan to keep the roof taped up while we’re in the middle of winter, way too cold to apply sealants and seriously consider a drive down south to Surrey Sunroofs. I’m not convinced that trying to fix the problem myself is a viable long term solution as I plan to keep the car for at least another 4-5 years and given the widely experienced framework issue I don’t want to live with the worry that it may go at any time.
I would suggest you seal the roof (use heavy duty polythene, any nicks and water WILL find its way in), dry the floor mats indoors, and get a domestic dehumidifier to work in the car ASAP. They are very effective in a confined space at pulling moisture out of carpets, etc. (see photo). Just make sure you warm the car up and keep internal temp above 12C as they don’t work so well in the cold.
Let me know how you get on. Don’t know your location, but this is a real pain in the midst of a Scottish winter! I’ll keep you posted. Good luck,
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