brakes still work on car. must push extremly hard on pedal to stop. Master cylindar is full to Maximum line. when you push on peddle, RPM's pick up, let off on peddle RPM's drop back. Peddle travel is very short before going rock hard.

Whats up? is there an electrical sensor out?

 

brake booster

 

can it be the sensor in the vacum line, gone bad, sticking, or replace the booster?

 

open your hood and look at the vacuum line coming off of the booster, take the check valve off (the plastic piece in between the 2 lines) and blow into it it should only blow through one way, if it doesnt blow through at all the valve has gone bad.

i havent heard of too many boosters going bad but it is a very good possibility