Water-logged Audi-mystery

Hi Guys,



My 1998 Audi A-4 Quattro, has developed an unusual leak from the air-conditioner…it intermitenttley pumps water into the passenger’s side of the car. The water actually trickles down from behind and underneath the glove box, at the inside corner of area where the feet of the passenger are normally positioned. The first time this happened, we were on a trip to San Francisco from Cambria CA. I sat on the passenger side and my significant other drove. There was so much water on the floor board, on the mat and underneath it, that my pants wicked the water up my legs and by the time we got home my legs were wet up to my knees!

We have asked a few German car guys (owners) about the mystery and were told by one, that since it was intermittent, it might be condensation freezing and then plugging the drainline on the foggy days we have here. The theory then was, that the usual overspill-water that one might see under the car when the air conditioner has been used, was pumping into the car instead of down the drainline when the line was frozen.

Well, that theory may not be the answer because now it is a constant happening, if I use my air. If I do not, then things stay dry! But it is summer, and I like my cool air.

My significant other owns and operates heavy equipment, as a business. He is not a foreign car guy. He is a Ford man. However, in frustration, he did put the Audi up on his hoist at the shop and tried to see the drain line…but no luck. It is apparently inside behind and underneath the dash, along with the entire air conditioning system! Could this be another one of those proverbial Audi “gotta pull the engine to get to it” problems? Do you guys have any ideas about what the source of this unusual problem might be…and any simple, affordable fixes? Ha Ha Ha…

I do love my Audi. It still looks and feels like a new car. It has 142,000 miles on it and I plan to get the 300,000 one should get from a good German car. I am a single, 50 something working girl and I cant afford a new one. Like most German cars, it has been very expensive to repair. And even though its been a good car, to me, its a continuous source of frustration for my friend, who has no patience for German autos! I think he’d like to have me trade it in on a 2010 Ford Mustang Shelby GT 500!

If you have any advice I would love to talk with you about it or at least get an email answer from you and your sources.



Keep up the great work Guys!

Thank you.

Deborah Cox

It’s most likely a plugged air conditioner drain line, shouldn’t be hard to clean out for someone who knows where it is.

Usually that drain is a black hose sticking out under the car near where the passenger puts their feet.

The two often recommended cleaning methods are:

  • Compressed air from the drain line. Don’t use too much pressure as it can pop the hose off the other end, Not easy to get to.

  • String trimmer line pushed up that drain hose. Go easy there too and don’t substitute anything sturdier, as it can damage the evaporator.

I have a '98 ford escort and this same thing started happening last week. took it into the shop and they tried to get to the a/c drain clog but couldn’t reach it. would have to remove the dash to get to it, which costs more than the car is worth. we don’t typically run the a/c but it pours water just turning on the fan (even at warm). I’m thinking about getting a roller paint tray liner to collect water. Anyone know if this will affect heat come winter?

Do NOT blow air INTO the drain line. You will just blow the gunk into the A/C system.

Use a shop vac instead. If the debris doesn’t clear immediately, run a wire up the drain hose carefully along its side and maybe scrape it around the hose.

but be careful not to push it up so far as to hit he A/C components - maybe 6 to 10 incehes max, depending on the car.