[cooling] low on water, but not thirsty

[foxxinabox at wideopenwest.com (Foxx (in a box))]

   noticed that my 8v seems to like to get rid of it's coolant. i can 
fill the tank up all the way and it'll usually be down to about 1/4" in 
less than two weeks. after that, though, it stays at about 1/4" and i 
have no problems cooling, even on warmer days (usually stays below 
half). don't suggest cracked bottle because i have swapped that out to 
no effect. the car does not blow steam out the pipe (no smoking) nor 
does it leave puddles. i cannot seem to locate the source of the missing 
water (no, it's not mixing with the oil, either). could a bad reservoir 
cap be to blame? i'm thinking also heater core (as steam) but it 
defrosts perfectly and i cannot smell antifreeze. ideas? thanx.

-- 
  /\_/\	  Foxx (in a box)
< o o >	  http://foxx.tripod.com
   \ /
    ?