Brake pedal hissing when pressed after VW service for brake fluid

[MK4_20VT]

Hey guys, my brakes suck now after the full service inc fluid change, i can get the pedal halfway before the car wants to stop & then it keeps going before its stops about 2inch before it can go no further

When the pedal is now pressed, i get a hissing noise

When the engine is off the pedal does go rock solid after a few pumps

Got to take it back tomorrow.  Any thoughts on the cause?

Thanks
Jay

[Chris.]

Needs bleeding again....Air in there somewhere.

Guess if pedal hard when engine off....hold pedal and start engine pedal sinks?

[bacillus]

Sounds to me like the servo vacuum line is leaking somewhere...

[MK4_20VT]

Right, did some more tesing.

If the handbrake is on, the pedal is better
quickly double pump the pedal & it goes back to how it was.  like i can stop, nice & firm

if I apply the brake like you would when slowing down to a set of lights, the pedal just keeps on going down until it stops past half way of the pedals travel, feels like nothing is on the end

Jay

[Wayne]

Servo pipe split or you have air in the system