Subject: Re: Coolant Useage

[Tom Winter]

Ian - There were only two times I've experienced coolant loss like the slow
vanishing you are describing are the following:

1. '87 5000 cs tqa: coolant seemed to be evaporating, with very minor
refills needed to keep car topped up, this went on for a bit, a month max,
with no weird smells, no coolant in the oil (noticeable coolant, at least)
until, WHAM! I blew the head gasket while winding it out. Soooo, there was a
small head gasket leak that wasn't noticeable (at least by me) that lasted
for a while. I hope this isn't your problem.

2. '95 S6 Avant: the lower coolant  line from the turbo to the engine had
not been tightened correctly, the loss was minimal, no puddling under the
car, so I lived with it, without knowing that the line wasn't tight. Of
course, such leaks tend to grow, and finally there was enough coolant coming
out for me to pin-point the source and resolve it.

I draw two lessons from my experience, which may or may not apply to you.

1. head gaskets may be leaky and it can be very tricky to know this until
they fail. Although excess pressure in the system is an strong indicator of
major trouble to come.

2. even when all coolant lines seem tight. They may not be.

It sounds like you've addressed #2, and I've heard some owners say that
their cars have a similar appetite as yours for coolant, an appetite that
they cannot explain and which has led to no troubles as of yet.

You say you had a new water pump installed. Was it tightened correctly? That
could be a hard to pin-point source of leaks, too.

Good luck,

Tom '95 S6 Avant