2 days ago I was racing (it was fast) and braking to.. after that the brake pedal felt and brake worked only after pushing the brake pedal very hard.. after that I changed brake fluid and pumped out air from brake system, but it didn`t help.. after that i changed rubbers in this thing (I don`t know what is it called) but it didn`t help... some say that it could be vacuum problem, but others resist, thay say that if it is vacuum problem, the brake pedal would be harder, and wouldn`t fall down..