Coolant mystery!?
 

Hi

I am new to the forum, but have read many posts on here trying to find an answer to my new found problem.

I have a 2011 S5 4.2 V8 and a few days ago I suddenly got a warning that coolant level was low. It was in fact empty. I filled it up and saw no leak. Drove the car a short distance and when I came home all looked ok and still no leak to be seen.

The day after I took the car again and when I came home again I checked and the expansion tank was empty again! Coolant looked like it was boiling, but assume that is pressurized air trying to get out?

The car has now been at a reputable workshop and they experienced the same thing. Rapid disapearing coolant and an alarm. They then filmed it up again and took it for a short spinn and when they came back level looked ok. They pressure tested the system three times and all looks great. No leak found. They also checked for water content in the exhaust and that all looked good. Oil also looks ok. So seems it is not going in to the engine either!! They have no clue where it goes! It seems to hold the fluid when you don't run the car.

Does anyone have any idea on what is happening to my car?? A wizzard under the hood? Someone stealing it while I drive???

All input appreciated! Getting desperate!

Br
Per

07 , I have the same problem as well on an A8 (d3) 4.2 quattro
I am joining in to this thread as well

if someone can ahead some light from is experience on this problem

an oil lab test would tell you if oil its mixed with coolant.not any other test can be 100% sure if there is a mix (which in this case with no drips i would say its a mix).