Recently had brake fluid changed by VW dealer. Since then noticed that brake pedal "hisses" when pressed. Brakes do function & pedal does not go to floor. Most noticeable when stationary or at slow speed, but can hear at higher speed. Could this be something needing further bleeding (ABS or servo?) or a sign of a vacuum leak?. Brake pedal goes solid with no hiss when engine is off. There is no hissing noise when brake is not being depressed. Checked hoses and nothing obviously perished.
Anybody had this problem and know the fix?
Thanks!
