The car only has 45k miles on it. its losing coolant at the rate that requires me to refill the tank about every 3 weeks when the sensor on the dash comes on. The dealership has had it for almost 2 weeks and cant find a thing wrong to explain the loss. They did a hot and cold leak down test and those came back fine. Put dye in the coolant tank and cant find a thing with that either, no signs of leakage anywhere. No sign of any dye in the exhaust and no codes have been thrown on the computer. The car runs like new, no issues except to continual loss of fluid that has been going on since late october. Ive gone through over 1 gallon of the coolant, so 2 gals of the mix. Not a sign of leakage anywhere ever, and so signs that the coolant is getting into the engine. ANy ideas?

 

I have the exact same problem, Seriously I just refill it, but that god awful beep, beep, beep is the worst sound in the morning. I heard it might be a water pump in the back of the engine that needs to be replaced. There is a slight leak and it drips directly onto the driveway! Anyway if they give you an answer please tell.

 

Its a big mystery as to where the hell this coolant is going. They have checked everything supposedly. They have even had in special audi techs to look at it. Guess these guys travel around and look at issues on cars. They mentioned that the guy was out of the country the first time I took it in. They say that a couple of techs from audi have looked at it.

 

I had the same issue and it turned out to be the auxillary/secondary water pump leaking. It only got worse as time wore on and I finally had it replaced.

 

Yeah it's probably the auxillary pump. Shine a flashlight under the intake manifold and see if you spot some crusty pink crap. If so, there's your problem. Also, if it is leaking get the relocation kit installed when you have it fixed...it'll save a lot of time later on.

 

I wish it were so simple, but you would think an audi dealership would find such a problem in the course of 2 weeks. They even have the dye in there and cant find anything anywhere. I will throw the idea at them and see what they say, but im sure they have looked there. No sings of coolant leaking anywhere, and they have torn part of the car down too. Cost me $450 just to do that, not sure what they took apart but they said they had to tear it down so they could see the engine and turbos better. That is a place that is notriously responsible for such problems isnt it? I think ive heard of others having the issue. Maybe I will get lucky and thats what the problem is.

 

How long did it take to get worse? Mines been doing this now for about 5 months and has not gotten any worse. Still losing at the sam rate. If that part is bad, wont you find resude around it or leaking to somewhere else in the car? In my case its like the coolant is getting burnt up somewhere.

 

most common leak is under the plenum on the V6 so cant be detected and it dries up quick with engine heat ( they should use a dye to find the leak ) but that = $$$£££

 

two most common leak causes are:
- auxiliary pump mentioned above
and
- crack in expansion tank ($25)
Check for spots becoming yellowish toward the bottmo of the tank...
yeah you would think a dealer would have found the cause in 2 weeks but my experience with dealers is not positive so I would suggest you c heck the above two and then take it a good Indy shop specialiazed in Audi.

 

thanks all for the advice. Going to call tomorrow, saturday and hit them up with questions about some of these problems you all mentioned. Really does sound like it could be that aux pump.