I noticed in my 13 Jetta when going through the car wash I would get some water splatter. I can re create this with a garden hose pressurized as well. Only happens with the sunroof cover open. When watching it the water comes into the channel with enough force that it then splatters out of the sunroof drain tray and into the car. The drain are all clear and everything visually looks good. The sunroof seal look good i did use a rubber seal conditioner on it to see if that would help. When Googling this you get answers from that's totally normal to the entire car is junk and to scrap it. I've only owned a couple of cars with a sunroof so I don't have a lot of experience with them. What do you guys think?
How water proof are sunroofs
- Thread starter wheelman
- Start date
All of my cars have had sunroofs, none of them leaked. Here's a short list:
1981 Toyota Cressida
1986 Mercury Merkur
1999 Jeep Grand Cherokee
1999 Caddy STS
2008 Caddy DTS
2014 Mercedes E350
2018 Mercedes E300
1981 Toyota Cressida
1986 Mercury Merkur
1999 Jeep Grand Cherokee
1999 Caddy STS
2008 Caddy DTS
2014 Mercedes E350
2018 Mercedes E300
- Joined
- Feb 3, 2023
- Messages
- 70
Yeah, have had many, many cars with sunroofs over the years and never had this. I even had a 2012 Jetta and never leaked. Not sure why closing the cover would stop the leak This is not "normal". I mean, if you hold a pressurized stream close enough to the seal yeah, I'm sure it will leak, so don't do that. But any normal car wash won't be that high pressure or close. I hand wash mostly but with a pressure washer, no issues. I have used many a touchless wash over the years on some of my commuters, never leaked.
How did you test the drains? They may be fine if you just pour a cup of water but there's a lot more volume to a hose or car wash, they may be blocked slightly. I'd try to blow them out with compressed air to start.
How did you test the drains? They may be fine if you just pour a cup of water but there's a lot more volume to a hose or car wash, they may be blocked slightly. I'd try to blow them out with compressed air to start.
They will not leak 
Not very "waterproof", especially as the seal ages and shrinks -- on my Volvo it's a common problem to have a sunroof drain come unattached and allow water into the interior. A LOT of water is flowing through that drain - an unattached drain means the interior will get very wet, soaking several inches of foam and possibly pooling in the back.
A downside of poor sealing is wind noise, particularly whistling in the rain.
A downside of poor sealing is wind noise, particularly whistling in the rain.
Be careful if you choose to use compressed air. You run the risk of blowing off the drain tube, see above post for the results of that.
Better choice is weedwacker string.
Better choice is weedwacker string.
I would not expect a sunroof leak in a car wash.
I checked all of the drains with weed Wacker string and they are all clear. It doesn't leak in the rain even a hard rain only when pressurized water is sprayed directly over it. The car was had enough pressure and so did a hose with my finger partially over the tip to cause pressure. The water comes in and splashes in the drain and then will spray out into the cabin. It's not a lot of water but it's enough you feel it hit you. With the cover closed the back side of the cover catches that little splash and it doesn't enter the cabin.
Given the explanation, I would suspect an improper seal. Visually it may look good, but I would try pressing it in again. Maybe it’s out of the channel and deforms when the glass presses against it.
Did you try the hose in various locations around the seal perimeter? Is it just one location that does it or several?
It may not be the seal to glass interface that leaks, but seal to roof. Maybe there is rust that lifts the seal and creates a gap? I would probably try to remove the seal at least partially in the spot that leaks to see what’s behind.
Did you try the hose in various locations around the seal perimeter? Is it just one location that does it or several?
It may not be the seal to glass interface that leaks, but seal to roof. Maybe there is rust that lifts the seal and creates a gap? I would probably try to remove the seal at least partially in the spot that leaks to see what’s behind.
Cheap fix for leaking sunroof.
My daughter's 2004 Mini had the drain tube come off the fittings. Had a thunderstorm dump a bunch of rain overnite, left a half inch of water on floor. Messed up navigation screen (computer is under passenger seat). Doing repair work as soon as weather warms up.
I would just use exterior caulking to seal it up and then pull the plug from the sunroof switch. Done and done, as I do t use sunroofs anyways. But OP may want to use it.
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I've never had a leaky sunroof on any vehicle. Keep the drains free of debris and condition and/or replace the seals when necessary.
i also treat the seals with a silicone grease once a year or so...
A power sunroof with a gutter system normally has a perimeter seal on the glass that is supposed to bridge the gap between the glass and the hole in the roof. This differs from most aftermarket sunroofs where the seal resides in a frame and is pressed against the inside edge of the glass by the latch system, theoretically forming a waterproof seal. Your sunroof seal was never designed to be 100% waterproof, but if yours has shrunk from age and uv, more water is getting past it then originally designed. If it's possible to replace this seal, or get a new sunroof panel, that should solve your issue.
How many of us, yes, us, know where our sunroof drains are?
The few times I've looked on any car, I've never located one.
The few times I've looked on any car, I've never located one.
