Porsche 911 UK Enthusiasts Online Community Discussion Forum GB

Welcome to the @Porsche911UK website. Register a free account today to become a member! Sign up is quick and easy, then you can view, participate in topics and posts across the site that covers all things Porsche.

Already registered and looking to recovery your account, select 'login in' and then the 'forget your password' option.

Help Please! 996 Coupe Sun Roof Drain leak at pipe connector


15 Apr 2014


Hi all, I've been fighting with a leak into the passenger footwell recently and today took the time to get the car jacked up, wheel liner off, interior trim stripped back and have a good look.

The problem is the nearside front passenger footwell gets wet when it rains. The car is kept on the drive, which slopes to that corner, so I suspect the rain water is pulled to that corner by gravity.

Things I have tried:

- replaced sunroof seal
- wiggled strimmer cable all the way down into the pipe from the sunroof end, at least 1m of it.
- removed a pillar trim, pulled back headlining to view pipe and connection (See pics)
- removed wheel arch lining, but I cannot see the drain port.

I can see that the strimmer wire is getting through the sunroof front n/s drain pipe and into the clear pipe that runs down the a pillar - there is no resistance and it doesn't come out wet. So I'm concluding from that that there is no blockage at least at the sunroof end.

When I pour water into that corner of the sunroof recess, it immediately starts dripping from the underside of the dash, about 6" from the firewall, right above the corner of the footwell floor.

With the headling pulled inwards and down from the passenger side of the car, the water drips down sidways off the headlining and onto the part I'm pulling down.

It's difficult to see, but the leak seems to be coming from the black plastic coupler that the clear plastic pipe joins to, seemingly about halfway up it - could it be cracked?

Anyway, do any of you kind gents have any suggestions for a solution - other than take it into a garage and hand over £500+++ ?!


  • 20220319_155511_140.jpg
    928.1 KB · Views: 1,658
  • 20220319_155535_609.jpg
    1.6 MB · Views: 1,658
it sounds like you have more than one leak .. the pictures show the roof leaking at the drain exit but you have water under the dash as well ?

the drain pipe runs down the A pillar .. disappears behind the dash then exits in the wheel arch area .

A leak under the dash is either this pipe has split .. and that's usually the corrugated pipe on later models which you don't have or the bulkhead seal has let go .. look at the a/c pipes next to the battery n/s/f .. the black panel and at the base it can leak .

Plenty of bitumen underseal to fix that leak around the base of that panel .

drain pipe split with this type .. i've never seen it .. possible but a new one on me .. you would need to remove it .. very difficult to check .

Your sunroof leak though .. that's not so good .. sunroofs like targa roofs are made from more than one panel and i would assume the sealant between them that side is now letting water past .

the only proper repair is heading off and sunroof cassette removed and inspected .. for me i would look inside the roof at the drain area .. anything i can silicone there .. you can smear loads of it on the inside but to be honest you can't seal a leak from the outside .. like a shower leak .. it needs to be stopped before the water gets in there rather than trying to stop from the outside which is just containing it .

I think if you wish a chat on the phone might be for the best .. pm me if so with a number and hours i can call over the next 2 days .. i'm off monday .. a bit easier that way i feel .

post here on the bulkhead seal .. http://911uk.com/viewtopic.php?t=149265 my last comment .

EDIT .. after reading this again .. it does sound like the drain tube has split .. you pour water in the sunroof and it drips under the dash then it has to be this .
Thanks very much for the info and link - I was hoping that the water was leaking at the joint between pipe and sunroof and then travelling down the A pillar before being dumped into the passenger footwell, but I think you're probably right - there isn't evidence of water inside the a pillar, so a leak behind the dash does seem most likely, as well as the one at the cassette joint that I can see. :(

I will get a helper tomorrow to pour water in whilst I'm soaking it up at the visible leaking joint, that should prove whether there's a second leak.

There is certainly no water making its way out into the wheel arch on that side, so it's all ending up inside the car somehow.

The drivers side front seems to drain well into the wheel arch, so I wonder whether the solution is just to block the leaking drain hole, park the car the other way around on the slope and let the other side deal with any water?

***EDIT: the front sunroof drains don't exit into the wheel arch, they exit in the door hinge area - see pics below***
Just realised I'd been looking in the wrong place for the drain exit - this diagram shows it (#2) exiting behind the front wing panel?

Is it accessible (maybe with the door open) without taking the wing off?!


  • pet_drains_coupe_656_252.jpg
    83.4 KB · Views: 1,601

To answer my own question, pretty sure this is the N/S/F sunroof drain exit close to the door hinge.


  • 20220319_224232_127.jpg
    1.1 MB · Views: 1,592
Ok, some more dismantling of the car later and I've found the main problem (Demort was right about there being two leaks! :thumb: )...

At the bottom end of the N/S/F sunroof drain pipe, it should connect to a right angled coupler that goes from behind the dash to the exterior, in the door hinge area.

Somehow, the end of that pipe in my car has completely separated from the right angled coupler! :pc:

See pics.

Does anyone have any ideas how I can reconnect it, given that it's about 8" behind the dash - with no easy access from above or below?! :dont know:


  • 20220402_145128_939.jpg
    574.6 KB · Views: 1,370
  • 20220402_145113_183.jpg
    419.3 KB · Views: 1,370
From the looks of the coupler it joins to, it seems that you just push the pipe into the rubber coupler?

That should at least make it easier, I think? Just need to align the tube and the coupler and get some downward pressure on it somehow?


  • untitled_141.png
    129.5 KB · Views: 1,358
deMort said:
EDIT .. after reading this again .. it does sound like the drain tube has split .. you pour water in the sunroof and it drips under the dash then it has to be this .

Sometimes i hate it when im right and this is one of those times ... it's not split which i couldn't see this type doing that but separated ... both are not good .

As you know .. there is simply no access to this pipe .. none that i can think of with the dash board in anyways .. I'll have a trawl through the manuals in a min to see if i can find anything but for the moment you have 2 options ..

One being a total removal of the dash and anything else in the way ..

The second .. using butyl or silicone sealant and seal the drain at the top so that water can't go down the pipe .. you would then need to never park the car in the wet with thats side on a downwards slope.. so a bodge at best .

How this could have happened is beyond me .. it would need to have been pulled upwards at a guess .

I'll do some research later .
Thanks again!

My next thought was to take the gloves box out and see if there's any access there?

Would that be a waste of time?
First off .. next week .. the first 996 we have in and i'll have a look to see if i can think of or indeed see any possible access point .

I looked through the manuals of both 996 and 997 .. there is nothing listed for this pipe .. it's basically one of the items thats fitted first in the building of the car .

With the dashboard out you have a large metal frame .. that pretty much covers this area hence atm im of the opinion its dash out and then this frame out .. thats a ... rather large job shall we say not not really a diy job ..

As per my ratings it would be a 10/10 diy job ... not every mechanic would even be willing to tackle this .

off hand .. glove box out wont help .

Image below i took about 17 years ago of a 996 i had the dash and this frame out to replace the wiring harness .. now this was a LHD and you will need to enlarge the image but you can see this pipe is still not visible as it's going to behind the sound deadening ... the metal frame covers this .. look on the n/s/f and you can see the frame fixings .

For now you need to leave it with me .. if i've not replied by the middle of the week then pm me to remind me .. i get busy at work so forget at times .

Best i can offer atm as i need to look at one .


  • tracker2_157.jpg
    71.7 KB · Views: 1,274
That's great info, thanks!

I think I may have found a rather cunning way of fixing this, but I'll report back to let you know if it works or was a Baldrickesque failure! :thumb:
@DeMort - great pic of that LHD car!

@OP - not sure, but if you remove the glovebox & that Air vent pipe, you might have more access - just be careful with the screw for the Air vent pipe, to ensure it doesn't drop down the pipe.

FWIW I had a similar leak at the other end of the drainage channels. I was able to dismantle it & repair using some sealant. It was a bit fiddley trying to remove the connectors, but I'd expect the ones at the front can be removed in a similar way, in which case this approach might work for you. See
If you were to thread a stiff wire or similar down the top pipe do you think you would be able to then thread it a little down into the separated bottom pipe? (you'd know if its worked using your scope)

If this works, do you then think you would be able to push down somehow on the top pipe so it then locates into the bottom pipe (or vice versa)?? Just a suggestion....
Space Cadet said:
If you were to thread a stiff wire or similar down the top pipe do you think you would be able to then thread it a little down into the separated bottom pipe? (you'd know if its worked using your scope)

If this works, do you then think you would be able to push down somehow on the top pipe so it then locates into the bottom pipe (or vice versa)?? Just a suggestion....

Had very similar thoughts! Will report back if I figure it out. :thumb:
Partial success - first pic shows copper wire inserted into opening of grommet.

Second pic shows 8mm ID pvc pipe nestled against opening of grommet.
I just need to be able to push the pipe into that grommet to run the new pipe, but I cannot get it to push in, the hole pipe and wire just bend!

Already tried plenty of lubricant and cutting the end of the pipe at an angle?

Any ideas?!


  • 20220405_212354_887.jpg
    179.5 KB · Views: 1,135
  • 20220405_204822_149.jpg
    236.4 KB · Views: 1,135

New Threads

Forum statistics

Latest member