Brake pedal hissing......

[VAGMAN2]

Hi

I have a 2000/TDI and for the past few months, the brake pedal has been hissing/making a whistle noise (!!) sometimes, when you depress it. It seems worse when the car has been standing for several hours. My first thoughts are is there air in the system??? The brakes were bled 3 years ago.

Anything I can do to check/diagnose the problem/fix???

Thanks-in-advance!

[NickPicks]

The book says you should change brake fluid every 2 years anyway.

Is it a hiss, of could it just be the squeak / rub as the pedal moves against its bearing?

[nevo]

Sounds like your servo is leaking vac on the pedal side,for get about bleeding the brakes, as air in the system is only a few air bubbles there's no pressure in there!Although as the previous poster says fluid change every 2 years.

[seancullen]

hi had the same problem with my a3, turned out to be the hose from manifold to pressure the braking system was leaking air. changed the hose and everything was fine no hissing noise. hope this helps