I have serious brake trouble on my 1.9 tdi 2005 B5 estate.

The brake pedal is suddenly travelling halfway down on the initial press of the brakes!

Both front flexi pipes have been replaced along with the master cylinder to no avail. The pedal is solid with the engine off and goes to the floor with it on. This is not the usual creep down found on diesel cars, the pedal can be solid, but if you leave it alone and then apply it again, it goes right down.

It has been bled umpteen times, in a variety of manners.

Does anyone know if there is some sort of vacuum valve?? or pressure relief?? in the system???

I am at my wits end.

It hasn`t been to VW yet, but so called specialists have failed to come up with an answer, and I would rather spend the money to get it fixed, rather than to have someone LOOK at it.

Much appreciation if anyone can help with any clues!!!

Thanks for your time.