Brake Pedal's Journey to the Floor A Guide to Diagnosis and Repair

I have an issue with my brakes where the pedal goes to about 2 inches from the floor before the brakes engage to slow the car. After bleeding the pedal seems hard until I start the car and then the pedal goes slowly to the floor. Can't find any leaks and the fluid level in the ... The pedal going down SOME when starting the engine with a power brake booster is normal, but the booster is making the air-in-the-system problem worse. The brake booster or master cylinder might be going out. Look around there and make sure the vacuum hoses going to the booster are good. After I start the engine though, the pedal has no pressure and goes to the floor. Yes, the new caliper is mounted correctly with the bleed screw on top. The pedal will go half way down, like it's suppose to, then I feel a release of pressure and it goes to the floor. When it goes to the floor, it doesn't stop ... Either you have air in the brake lines somewhere or the master cylinder is shot. As GBAUTO alluded to, if the master cylinder was allowed to go ... If there's no brake fluid on the ground and the reservoir level isn't going down, then the problem is a failed seal in the master cylinder. Some things I would check: 1. Is the fluid level dropping in the reservoir? Check for leaks throughout entire system. 2. Look at the fluid in the reservoir and ... The symptom sounds like a master cylinder(mc) seal is bad. If you don't have a puddle(a leak) this is the only thing I can think of to help.