Can Master Cylinder Be Bad Without Leaking?

I've replaced the front pads, the rear brakes and wheel cylinders, and bled the system. I still have the same symptoms: the peddle seems good, but the stopping power is bad and when pushed hard the peddle is spongey. The vacuum is good, and there are no leaks from the master cylinder. Can it fail internally and cause problems that are not readily apparent?

Thanks.

f100.

Yes, Especially after doing a brake job on a higher mileage vehicle and pushing the pedal all the way to the floor to "pump up" the pedal. The debris that accumulates in the bore settles in the part that rarely gets used. Run the seals through that debris and they can be junk after that. Its a 50/50 thing. Sometimes there isn't a problem and sometimes there is.

A similar feeling can happen until the pads are seated into the rotors.

Bad calipers or hoses can do the same thing.