Hello all Our 1999 Forester SF is making a noise like gently trickling water at start up, from behind the dash, heard inside the car.      The ‘trickle’ increases with engine revs and goes away after a minute or so. It does it every time, and this is a fairly recent situation. There is no apparent external liquid loss nor wet carpet. I’m going to make a closer  inspection soon, check coolant levels and burp the system, but  wonder if anyone has an idea about this. Stock