pocketchange

This is a first for me.

OK.. we did have half a foot of rain a couple of days ago.

Went out and found this issue, just wondering where the water came from.
No leaks through the sunroof and nothing from the other typical locations.

I'll fix it if someone will point me in the right direction..

Thanks,
pc

jfrahm

Cowl drains, when the cowl fills up it comes out the rear AC vents. Fix it quick, it'll drown your TCU. Audipages has a procedure.

silverd2

Just a guess from personal experience:

Take flashlight and look in the air tunnel behind the rear center vents.

Thanks to a bad seal design (foam) in the fresh air plenum where the AC air intake box mounts to the cabin wall, clogged rain drains or a steady downpour can let water seep into the center air tunnel...still happens occasionally on my car, even with cleared drains (rain and AC...MUCH worse when clogged).

Mine tends to stay in the tunnel and mysteriously drains out somewhere (not in the carpet) after hitting the brakes a few times or driving downhill. If I turn the fan to max (or auto setting does the same) before letting water "drain" forward, it will blubber out on the carpet on the center tunnel.

In mid 2001 model year (mine was made before the change), Audi FINALLY redesigned the intake box slightly and added a solid rubber seal where it should have been all along...real dumbass design flaw.

Worth lookin' at.

silverd2

P.S. I suppose it's possible that the same water source could make it to the floor vents under the front seats(?)....none that I've even noticed in mine, though.

pocketchange

Curious that the drain vents from the A/C are not plugged and dripping without a problem.
Side drains under front doors are flowing without issue.. pc

jfrahm

center cowl drains. They drain into the trans tunnel behind the engine. Scroll 3/4 the way down this page for the unclogging procedure:

http://www.audipages.com/Tech_Articl...tordrains.html

You poke a tube in there and blast compressed air to shift out the leaves and gunk that are clogging the drains. I had the same problem and also had good flow from the AC evap drains and cowl side drains. After you get it flowing you can wet vac out the crud.

silverd2

As I stated before, because of Audi's stupid mistake with a foam seal (pre-2001.5), heavy downpours or car washes can still let rain water enter the vent tubes. Keeping all drains clear, however, minimizes the problem.

Note: In general, only the rear sunroof drains get clogged (have never had to clear fronts)...the only ones that matter. If this was the source, you should see new moisture tracks on the headliner, too.

Past clogged rear sunroof drains on my car only leaked into the interior when rear water pooling (after parked in significant rainfall) has been thrown forward when hitting the brakes hard shortly after starting to drive, spilling out sunroof controls or headliner near windshield (never in the rear for me)...careful driving, at first, allows it to drain out the front open drains.

BrianC72gt

A flooded cowl will cause water to infiltrate the air ducts, saturate the radio, the passenger's footwell relay box, and come out everywhere. Ask me how I know. I had a worst case scenario about 9 years back. It cost me a TCU, ECU, Fuel Pump and a couple of coils.

For the rear center air duct, I removed the back plate then fished the shopvac hose - necked down to a length of heater hose - with duct tape into the vent tunnel and sucked out all the water.

There are four drains in the engine bay cowl area. Two straddle the bellhousing with a <a href="http://img4.wikia.nocookie.net/__cb20131002182123/community-sitcom/images/3/30/The_Paper_fortune_teller.jpg" target="_blank">fortune teller</a> endcap. Take them off and you MIGHT get critters crawling up the open ends. Leave them on and they may (will) clog, flood the cowl and cost you a fortune. Those two endcaps make a lovely floral arrangement in my tool box.

There are also two tiny (pencil sized) drains at the outside edge of the cowl that exit via a rubber nipple into the top of the wheelwell. Pinch your nipples. Oh, and clear or remove the ones in the wheelwell as well.