Got a question for you guys. Here's the deal, my brakes work when they want to (most of the time, thankfully). I have checked all the lines, no problems. Bled them, and topped off the fluid. Was wondering if it could be a master cylinder problem or what. Sometimes I will be sitting at a light and the pedal will go to the floor. At this point I can pump the brakes and sometimes it will return to normal operation and sometimes not. Any help will be aprreciated. Sorry for the long post.