1996 cougar
4 wheel disk brakes-ABS
Im having a problem with my brakes

. I can get the front brakes to work but not the back


. The pedal feels like it goes farther down then it should before i stop. i bought new master cylinder, front and rear calipers, proportional valve, and flushed the system

. pedal is hard when i start, but after i bleed the screw it takes 1-2 minutes before i get pressure again

. Pressure will stay and no sign of fluid is leaking except "VERY" small leak on brake line. What could this be??????