HootingOwl

No sunroof. It is almost certainly the rear windscreen. I have stripped the trims and can see evidence of water ingress, and the screen can be pushed out from the body by hand. This also explains why there is a high pitched wind squeal at speed - sounds like Sooty and Sweep going at it hammer and tongs.

Update.. Just in case anyone is suffering from insomnia. Pretty certain it is the rear window bonding. If I push on the inside of the glass at the top., the screen moves outwards away from the body. This cannot be right. Further stripping back and new gaskets on order. Windscreen fitter will be summoned when foam lays and rubber gaskets have arrived. Car breezed through MOT the other week but needed 2 new tyres.. Have a camber issue at the front but the excellent specialist I use knows how to manipulate the front subframe to sort the geometry out. Had the wheels refurbed in Audi Anthracite...

Hello... Recently joined the forum and thought I should introduce myself. I have recently acquired a 2009 3.0 sport quattro with 74k on it. It is in great condition but needs a few minor things sorting out. Also have a 2009 TT Tdi from new, and a Transporter van. Running out of driveway space. I have VCDS or VAGcom as it is sometimes known and am more than happy to let other people use it. I am very close to the M5 M4 M32 motorway interchange on the North side of Bristol. Also have the update discs for MMI 2G to the latest and last revision levels. Again, happy for people to borrow them.

Car is new to me. Got it last October and it appeared dry and did not smell of damp. Bought from a work colleague of my Brother with a good and known history. Noticed the damp about 2 months after purchase despite some heavy rain. I took the rear headliner trim off and there was moisture behind it. Will take down remaining trims this weekend to inspect further. Whilst driving along the M6 at a decent pace, I noticed a loud whistle coming from the back window... It sounded like sooty and sweep up to naughty things... Makes me think that the seal has been breached. Looked at the parts and it shows a moulding strip at the top of the rear screen. Going to fire up elsawin and look at the replacement procedure. Fingers crossed....

This sounds facetious but really isn't.. But have you checked that all the lights work and are of the same intensity? Dunno about the A8 but some systems are picky about the resistance of the bulb and show a fault even if the bulb appears to be working. Hence led replacement bulbs have ballast resistors to fool the warning circuits into thinking it is a regular bulb. Check the connectors for corrosion and water ingress. Check the earthing points. Does it say what bulb is faulty? What year is your A8 a d what type of lamps? Xenon? Adaptive?

Retrofitting an SCR system is not really a viable proposition for a passenger car. The systems in the above link are for buses and HGVs...the cost of installation is around 20k and only certain chassis and engines are supported. Coach operators are fuming as they are looking at having to buy new coaches at 250k to 500k a time. Might be time to swap it for that W12 or V10 S8.

Unless the previous owner ticked the in-boot hot tub option, I have a substantial ingress of water into the wheel well. Most of it appears to be coming from the rear windscreen, passenger side {RHD UK car} and then soaking through the parcel shelf. I am going to strip the trims back next week for a closer look, but has anyone else experienced the bonded windscreen seals failing or is it more serious like a body seam? Thanks