Bladerunner

Anyone have this before?





The right side boot behind the wheel arch is soaking wet. I’ve checked the boot seal, it’s newly replaced and seems ok. Any ideas how the water is getting in?

I’ve ruled out the rear window seal failing, as the car interior and rear parcel shelf is dry.

It is missing one of those small boot stops near the rear light, could water be getting in through that hole or maybe the seal which meets the metal here?





Any thoughts on this appreciated.

Thank you.

MP4.2+6.0

Check sunroof drains.

Bladerunner

Thanks MP4. I just saw a video about it.

It’s for a D3 so I wonder if the D4 even has rear drains, did the design change? I’ve not got any wet in the car though and I thought these went through the rear pillars, not near the boot.

I just noticed my fuel filler cap had water round it, the small drain there appeared to be blocked, so I poked it with a plastic tube, it went in quite far but didn’t come out anywhere I could see, it’s behind the wheel cover. I hope it doesn’t go into the boot.
It if did, could it be that?

Hybrid Paul

I have had issues with water in the boot, and in the rear seat/parcel shelf.

After a lot of false dawns, it turned out to be the seal in the rear screen, along the top - where there is no sealant as such it is direct applied to the metal. as the car is fairly sir tight, over time slamming the doors creates air pressure that breaks the "seal" along the top of the window.

Water runs down the c pillars, down the back seats and in to the boot. Check the rear seat belts for damp - pull out tall the way. Check the base of the c pillars and the rearmost part of the parcel shelf. Mine ended up with a lot of mould (I was out of the country for 3 Months so car was standing in a combination of torrential rain and then hot sunny days). Also take the florr trim out, and check in the wheel well for damp.

I used a company in Essex called New Again Ltd to test and fix. It cost quite a lot, but they did fix the leaks and had to take a lot of the trim (rear seats/door trim, headlining, c pillar trim, parcel shelf/all the boot trim etc to find and then dry our/clear up the mess.

MP4.2+6.0

I doubt sunroof drains have moved from D3 to D4. Can always try some water down the rear drain holes in sunroof frame with a turkey baster and see if it hits ground or not. Will exit somewhere in that wheel corner area.

Not sure on drain you were referencing . There is usually a small drain tube at bottom of fuel filler rubber boot to deal with gas hose overflow.

Yes, could be rear window seal as mentioned in another reply.

Could also be trunk gasket seal.

One that came up a fair number off times now on D3 (besides the sunroof drains) are the tail lights. If you see condensation inside tail lights, be even more suspicious.

Bladerunner

Thanks MP4.

I’ve checked both front sunroof drains and they were fine. I couldn’t see the rear drains and even on a slope couldn’t get water to go towards the back of the car anyway.

I checked the rear lights and no water or condensation in them. I also used a small camera to check inside the area behind the lights and couldn’t see any water coming in.

It’s a new boot gasket and doesn’t leak as far as I can tell. I do wonder about the plastic around the boot. Is it sealed underneath?

Bladerunner

Just an update. Turned out to be a badly installed rear window from the factory.

https://www.audiworld.com/forums/a8-...-tint-3007990/

Hybrid Paul

Interesting. How did you narrow it down to this as a cause?

A8L_New_England

Just my $0.02... Somebody in the trunk with a flashlight, and somebody outside with a hose usually helps find these kind of leaks.

Bladerunner

The company removing the faulty window showed me where there was no bonding applied and the where water was getting into the vehicle. It was glass on metal along the top rim.