 soft brake pedal
Re: 1995 Windstar
About 3 years ago, I started getting a pulsing feeling in the brake pedal when braking hard. The pedal would also drop a few inches, but I could still stop. The pulse does not affect the steering wheel and I can't really feel it in the floor or seat. It is just a pulsing pedal and pulsing noise. At the time, I was told it was a valve in the ABS system that would cost ~$1400 to replace and that the rest of the brake system would continue to work, if I could deal with the noise. I dealt with the noise.
Over the last 3 years, the pulsing feeling in the pedal has advanced from only sudden hard braking to every time I stop. It doesn't happen at speed. Only when stopping. The pedal no longer drops while braking either. Now, it is just always spongy. This weekend, I replaced the front pads and inspected the front rotors and calipers and the rear drums. All of which looked fine. The master cylinder had plenty of fluid and showed no signs of leaks but I replaced it anyway since that seemed to be the likely culprit for a soft brake pedal. My braking distance seems to have improved slightly, but I still have a soft pedal. I bench bled the master and gravity bled all four wheels. The only thing of note was that the rear passenger side wheel never seemed to pressurize. Instead of spurting when I opend the valve, it would always dribble out, even after ~5 tries.
Could whatever is causing the low pressure in the rear passenger side wheel be causing the soft pedal? Something else? I have been driving this van since my family bought it new in 1994 and I have replaced/rebuilt the engine and transmission in the last 3 years. I am happy to continue driving this van until it falls apart around me but I am worried about the safety consequences of not being able to make a sudden stop in case of emergency.
Any ideas you may have would be appreciated. | 
