Brake pedal falling

[BeatDaSHO]

So I just put in a new master cylinder about a month ago. I was trying to diagnose this problem I was having and it ended up being the proportional valve. None the less, I have a new problem now. When I am at a stoplight, I can press the pedal to the floor. Even if you try pumping the brakes and then pressing it down, it still falls to the floor. Yet, when i'm driving, the pedal feels awesome and doesn't fall to the floor when braking hard. I'm not quite sure what it could. Maybe a leak? I've tried testing the booster by pumping up th brakes when the car is off and seeing if the pedal falls to the floor but it doesn't seem to. What do you guys think? I hope this new master cylinder isn't bad. Let me know. I am going to be working on the car tomorrow.

Greg

 

[rangerj]

About a month ago there was an extensive discussion about the tests for the power brake booster and the master cylinder. Do a search and read through the prior posts. Depending on how you bled the master cylinder you may have gotten air in the ABS pump.

Once you have read through the prior discussion get back to us with any additional questions you may have. rangerj

 

[Petersho1]

Read my post petersho1+master cylinder