Hi guys ,i just bought a 2001 Acura 1.7 EL which had no working brakes when i got it..Its has 4 wheel disk brakes.There was no brake fluid left in the master cylinder and the right rear caliper's piston was completely out because there was no brake pads left not even the metal nad the rotor was paper thin..I changed the 2 rear calipers ,rotors and pads,filled the master cylinder and tried bleeding the system.The front right and left rear bleed fine but the front left and right rear have no pressure.i disconnected the 2 main lines from the master cylinder to the abs box and there seems to be pressure from both.Could the proportion vave be stuck?If so any way to tell or can the valve be repaired?Could it be something else?Thanks

 

have you tried bench bleeding the master cylinder? And also I really don't know how to tell if a proportion valve is bad but there cheap at a local junk yard to get a replacement.

 

Master cylinder was the problem.I took the one from the parts car and all is good.