mgd-98.5A4

Sorry about the length, but I've tried many things and am stuck as to what to try next. I've even searched the archives (here and other sites).

Basically, when it rains, the driver's side carpet in my wife's 2005 A4 Avant 1.8 MQ (B6) gets wet. We bought it used as a CPO 3 years ago. At first it was just a musty smell, but since we park it in a garage at home and covered at work, it never got that bad. This year, we had to park it in the driveway and it got covered in snow several times, and a lot of rain fell on it. The driver's side rear footwell was really damp several times (due to slope of driveway, etc.) but even the front carpet was damp at times. Leading to my theory that the water is coming from the front, and not the rear sunroof drains that are commonly clogged.

We discovered a huge accumulation of pine needles and dark "gunk" around and under the battery, brake booster, computer box, wiper motor/linkage, etc. While still under extended warranty, the dealer cleaned the battery area out, and partially under the break booster, and cleaned out the front sunroof drains (work order didn't mention rears). Since the end of the warranty, I've cleaned gunk out of the area under the wiper motor/linkage area, and from under the front driver side wheel well (removed cover, etc.). I've pulled a lot of gunk out, but the carpet was still getting wet. Seemed to be worse when we drove in the rain, but it was hard to tell exactly. I have confirmed water easily drains from the area around the battery/computer box now.

I taped off the sunroof to prevent any water entering there as a test. Water still seemed to get in. i.e. I'm trying to remove possibilities.

Next, I pulled the driver's seat and rear seat, and tried to pull the carpet up. Man, what a crazy design. The 1-4 inches of foam underneath were soaked. Drippping soaked. I used a shopvac, towels, shammy, fan, etc. to dry out the foam and carpeting. The wires and electronics all look OK at this point. The foam under the gas pedal is darn hard to dry out since it goes under the center console and it doesn't bend/lift easily...

So, I'm at am impasse currently. What to do next. Any advice will be helpful. The carpet is already smelling musty - hopefully a good cleaning will remove that later. But, I'm focused on finding the leak and fixing it. I have yet to actually see where water could have come in the cabin, or how the needles/gunk could have caused it. All the *visible* grommets look intact. Nothing seems to be leaking when I pour water down the windshield. There is no evidence of water intrusion from the rear either. trim panels are clean, under rear seat dry, etc.

What's next Audi experts? Punt and take it to a shop and spend an unknown amount of $$ and pray they find it? Continue by removing the passenger seat, center console, and entire carpet to see if any non-visible bolts/grommets under the carpet are compromised? Dig into the dash to see if anything under there is compromised? I'm hoping my web searching has missed something.

Oh, I've also looked at the driver's door and the seals around the edges. They all look intact and not likely to be the source of the water. The inside of the door seems to drain well, and when it rains, I/we don't see evidence of water coming from the door into the car.

Thanks for any advice anyone can give!!

Mike

lyleswk

I believe there are 1 or 2 drains in the "bucket" where the battery is installed and assume they were cleaned out as well. I have never looked into them, but understand they are straight runs to the underside of the car vice the sunroof drains which exit in the front door jambs and by the rear wheel. If this fills up, it could seep into the cabin.

http://www.audizine.com/forum/showth...ghlight=drains

Also found this link...

http://www.audizine.com/forum/showth...ghlight=drains

And this one which may the most helpful in understanding all the drains.

http://www.audizine.com/forum/showth...ghlight=drains

mgd-98.5A4

Those are great links, thanks!

I'll pull the a-pillar molding and check that the hose isn't unattached. But, with the sunroof taped off, no water is going that route. But, perhaps there was enough water in the carpet/pad already to make it seem like more was coming in after I taped it off.

I think I'll also check the ECU box next too. An exterior check is easy enough. But removing it to check the seal to the sheet metal underneath will be a pain - the castity screws holding the ECU in and all. Oh, well, it's just work!

Failing that, I'm going to pull the center console and carpet and start doing some real searching under the dash area. I'll post an update as I go.

Ritz

If I had to guess, I'd say you're getting water pooling by the ECU which is then following the wiring harness into the cabin.

lyleswk

Never had to mess with it, but you may not have to remove the ECU, just work around it. I don't like removing things unless absolutely necessary. As one of the link notes, you can get to the battery pan drains from underneath.

aprice01

I experienced water coming from the drivers side footwell area after a heavy rain. Turned out to be from one of the screws which holds the wiper mechanism down (I had removed mine to repair a slow wiper issue). Verify that all of the fasteners are present and tight (I believe there were three).

mgd-98.5A4

I think the leak has been found. At least one leak. A body seal was cracked and needed to be "refilled". In the area below the corner of the hood, there is a body seam. Turns out that seam wasn't sealed and needed what looks like silver caulk. To be honest I turned to a body shop guy and he found it and did the refilling. So far no leaks in the recent rains. I'll watch it for a few more days (it's really raining in Seattle now), and hopefully it's been fixed.

I'll try to take a picture and post it, but really if you open the hood and look in the small nook under the corner of the hood (behind where the hinge attaches, you'll see where the body seam is. if it looks cracked in any way, water is getting in.

Thanks for all the ideas from everyone. As frustrating as it was, I learned a lot about the car poking around and investigating.

lyleswk

Are you referring to the area below the battery and heater hose connections?

mgd-98.5A4

No. Standing in front of the car, with the hood up, the far right corner - behind the ECU box, under the corner of the open hood. There is a body seam, and in our case, the body seam sealant was cracked.

lyleswk

Intersting. Something for folks to look for.

Thanks!