hi peps. Just a qwick question that im sure someone might know the answer to. I have a mk1 leon cupra on a y plate. every time the engine is started i get a constent hissing noise,but that changes to a high pitch sweak when the brake pedal is used. Once the sweak has stopped after 5 secs or so its back to the constent hissing. comment has been passed that it could be the brake servo but since found out there not cheep. Any other ideas or answers would be great.