Brake pedal won't pump up?

This is usually a master cylinder problem. Get under the car and look for oily residue drip lines on the inside of the tires meaning a busted wheel cylinder. A leaking cyl drains the fluid out of the master and allows air to enter. If the master lost fluid and got air in it it may still be good but you have to do all the steps needed to restore it to service after you rebuild or replace the leaking wheel cyclinders.