"ts" > wrote in message
...
> I've had to top up the coolant level in the radiator expansion tank on
> my Audi A2 today. The manual says it's important to maintain a 40% mix
> of anti-freeze to water but that you can top up with plain water in a
> emergency (which is what I did). How important is this ratio, and how
> much liquid does the tank hold? I probably put about a litre into it,
> and I don't want it to freeze with the cold weather coming up.

If you put a litre in, you've got a leak, which is a problem.

Bearing in mind the age (or lack of it) of even the oldest A2, that is
surprising. Have it investigated.

Regards

Jonathan