Q: Brake pedal goes all the way to the floor

A sinking pedal is often a sign that there is a leak somewhere in the brake’s hydraulic system. Sometimes a problem of this nature may render a vehicle unsafe to drive, as braking systems relies on sealed pressure to operate. I would thoroughly inspect all 4 wheels, and underneath the vehicle for any obvious signs of leakage. If no obvious visual evidence is found, I would then suspect a problem with the master cylinder. Master cylinders usually fail due to internal sealing issues, so a thorough diagnosis of your braking issue by a mechanic would be recommended.