Brake issue 1998 wagon

[impaladave]

Brakes just started going to the floor and not really stopping the car. Brake fluid is full. Didn't know if these vehicles have a proportioning valve that could be causing a problem or if master cylinder might be out????

[Airjer_]

First thing to do is completely inspect the brake system for any leaks. The reservoir may not be empty.......yet. Rear wheel cylinders can be a likely suspect!! If no leaks are found than the master cylinder could be a suspect.