I just got done replacing the calipers, rotors, and pads on my car, bled it all til the pedal felt good and had good pressure, got it all back together, turned the car on and hit the breaks, and the pedal lost all stiffness and when its being pressed in, a hiss comes from the pedal area, which i followed to be coming from something under the master cylinder i think ? any thoughts on what this is, i get all of about 0 breaking pressure right now and i need to get this fixed.

Thanks for your input.

 

i had a problem like that but i had SOME pedal action. but it was the Brake Booster. the bladder was ripped inside. so that was the hissing when i steped on it.

 

Ok, i exagerated a bit, i do have SOME pedal action, just not much.

So what does it take to fix the booster ?

 

A new one.

 

could not have sayed it better... haha..
its really easy. just disconnect the masterclynder and then the bolts holding it in under the dash (and the pedal assembley) its 4 --12-- bolts i think. u dont need to rebleed if you do it right.