Spongy Braking

[timofej.crift at att.net]

Here is one that has me stumped.  I recently acquired a
1999 A8.  The car has spongy brakes so I figured a bleed
would do it.  It has a recent fluid replacement and my
guess was that the monkey lads had at it and improperly
bled the system. Bled the brakes yesterday evening and
the pedal came back nice and firm.  While driving it
home the sponginess returned.  Has anyone had any
experience with air reentering the braking system from
any of the various points?  I am hoping that it is not
an MC, but some blackish residue in the fluid reservior
has me expecting the worst.

Cheers,

Tim Crift
timofej.crcift at att.net

'99 A8 (squishy-squishy)
'95 90
'84 CGT