hey, ive recently changed the rotors and pads on my front brakes on my eg5, i also did a brake fluid flush with all new fluid.
the pedal felt great for teh first 10mins, but it started to sink to the floor when pressed but if u pumped it, it would tighten up again, but then sink again
im guessing its the brake master cylinder thats gone.
what am i looking at? brake master cylinder, brake booster?

any advice would be appreciated