51 plate BMW 318i brake pedal gone rock hard n car won't brake any ideas ?

sounds like brake servo not working,-with engine off ,depress brake pedal a few times to exhaust vacuum, then with brake pedal pressed, start engine,there should be a noticable depression of pedal,if not then you need to check the vacuum pipe from servo to manifold to check for blockage also check one way valve which is usually at servo end of vac hose.

k
February 2011