I am working on the brakes, the pedal is going to the floor. We have replaced the master and the rrear wheel cyclinder and bleed the system. We have good fluid flow to all the wheels, but still nothing.
My car has an automatic transmission.
If the brake pedal is going to the floor even after replacing master cylinder and rear brakes you still have air in the brakes. You may need to use a pressure bleeder to push fluid through the system and bleed out air. If vehicle is equipped with anti lock brakes then you will need to put it into bleed function using a scanner so air can be bled out of it. Make sure you bench bled air out of master cylinder or you may not be able to get the air out of it due to angle it is at.