Wife came home with brakes smelling roasted. Appeared one caliper hung up. Replaced caliper and installed new pads all around. Bled brakes fine but on start up brake pedal goes to floor. Still took for a test drive and brakes are getting hot again. Bled brakes, master cylinder, and multiport block. Pedal builds and holds pressure fine with key in run position while bleeding but again on startup loses all. Any help or suggestions?

 

Any problems with pedal pressure before you did the initial repair?

Could be a brake line problem on that corner if you already replaced the caliper. Fluid could also be seeping past the seal in the master cylinder, which would stay in the system as far as I know and not look like a leak.

If you already checked the obvious stuff, I'd take it to a pro at this point.