Pedal Falls Away
WARNING: This page is about a different car, the 2011 RAM Pickup and 2011 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
A brake pedal that falls away under steady foot pressure is generally the result of a system leak or fluid contamination. The leak point could be at a brake line, fitting, hose, or caliper/wheel cylinder. If leakage is severe, fluid will be evident at or around the leaking component.
Internal leakage (seal by-pass) in the master cylinder caused by worn or damaged piston cups, may also be the problem cause.
An internal leak in the ABS or RWAL system may also be the problem with no physical evidence.