89 100 Radiator getting low fast?

[urquattro]

> In the past month or so, ever since it got cold, the radiator reservoir
> has been getting low very quick. I would drive it from home, then the
> warning light will come on. So I had to pull over, looked in the tank, and
> it's 1/2 empty. So I topped it with the coolant. Then driving home on
> the way the same thing would happen again. I don't understand how this is
> possible. I don't see any leaks or anything. I mean this looks like big
> time leak, but I don't see anything under the car when it's parked. Any
> hints/helps is greatly appreciated. The car is 1989 Audi 100. Thanks.

... if you truly can find no leaks at all then you may have a leaking head
gasket ... perhaps its the higher compression or something ... this seems
from my experience to be more common on the NA engines than the turbos
(AAMOF, my BiL's car is sitting in the driveway right now in that state ...
:(  You can pull the spark plugs and look to see if one or two look like
they have been steam cleaned.

That said, there are a lot of things that can leak and might not show a
trace of having done so.  Given your correlation to the weather change,
perhaps it is the heater core (of course your car runs hot coolant through
the heater core almost all the time even in the summer!).  If you haven't
changed hoses recently that is another possible culprit.  I had a hose at
the back of the head develop a pinhole leak that only occurred at certain
times.  If it hadn't sprayed on the exhaust manifold it may have been a
while before I even knew it was there!

HTH!
Steve Buchholz
San Jose, CA (USA)