Okay well here's my situation, the brakes on my camaro are going to the floor. The booster is fine and the master cylinder is new and not leaking. There are no line leaks I have checked thoroughly. None of the lines have air in them I have bled and bled and bled them with the same result. Now whats shocking is that when the car is off the brakes are normal. Like when you pump the brakes they get harder and harder to pump every time. (Good booster) and the vacuum us good on the booster and the Master Cylinder isn't leaking into it or at all for that matter. When you start the car the pedal goes down a little like it should (caused by the booster) but it goes to the floor with little effort. What is that all about? Someone told me that the brakes could be out of adjustment? How could you tell if they were or not and for that matter how do you adjust them? . Oh and the brake light is on. Not the ABS light just the brake light. Thanks for all help in advance.
~Tater

 

sounds like you have issues in the abs unit. maybe air, maybe wheel sensors are failing. try unpluggint the abs fuse and see what happens.

 

with the vehicle off, press the brake pedal and keep pressing it. Does it also descend toward the floor? If so, then you have a leak somewhere or bad master cylinder despite it being replaced. How are you bleeding the brakes? Please don't say you are simply allowing it to squirt out and hope to close the nut quickly enough to not allow air back in

 

When I unplug it what is supposed to happen? And I think your right craby I read somewhere that air in the ABS unit can cause this. I found a procedure to fix the problem and bleed it correctly yourself so that's where I'm headed next. If nothing else I'll take it to my shop which has a GM Tech II and let them do it . And no when you pump the pedal with it off it builds pressure and gets harder and harder to pump every time like it's supposed to. And no I'm not a retard I've bled plenty of brakes before. On this one I had my grandfather slowly press the pedal to the floor after I opened the valve, after he had it to the floor he would hold it there I would tighten it up and he would let go. Repeated this process multiple times on each wheel (front disc & Back drums).

 

Sounds to me like the master cylinder. Regardless of weather its new or not, it could be bypassing the fluid pressure internally. In this case there wont be a visible leak.

 

The light on, providing it doesn't pertain to the emergency brake at the time, means air in the system, or a pressure loss (fluid leak either external or internal).
Was it doing this same thing before with the old master?
Did you bench bleed the master?
While bleeding, did you make sure you didn't suck air in by letting the level in the reservoir go too low?
Did you check to make sure there's no wetness (sign of a leak) at the calipers and/or wheel cylinders?
Do you have disc or drums in the back? If drums, you need to pop them off to take a look inside.

 

x2 on the master cylinder. Not the first time something is bad out of the box.

 

That was the reason for my "did the old master act this way too". If it did, I highly doubt the new one would be bad too. If old and new are bad, better go buy some lottery tickets, cuz you're on a "lucky" streak!

 

I'm not sure about the old one. I made sure the reservoir was full the entire time. I just bought this car as a project...and trust me...that's what i freaking got. Let me explain:
1) Yes it has drum brakes, I pulled the drums off to look inside and guess what i found?!
2) Gear grease -.- . Both of the rear seals are bad!! YAY! and to top it off:
3) The front of the differential is blowing gear grease everywhere.
Soooooo I'm about done with it and I literally have only had it a week. So the entire rear end needs to be redone so while I'm at it I will probably get a whole new rear end. New Disc Brakes. But on the bright side...no brake leaks > .
Anyway, so the rear end is the next project...probably going to be a couple of weeks before that gets done. But it's okay because I found out it needed new brake shoes anyway...hey look at the good things right?
Ugh
Will get back to you guys and keep you updated.

 

Your soft pedal just may be because of the rear brakes then. If the self-adjusters (that thingy with a star wheel that's sandwiched between the bottom of the two brake shoes) are frozen stiff with rust, your rear brakes are going to gain more and more travel as the shoes wear down. More travel in back = more travel at the brake pedal, until.....