i just finished changing the brake pads and starter in my '87 Z28 Camaro -- starter works wonderfully, and the brake pads are on fine now...

But, now I have a problem: After I bleed my brakes the pressure is fine and the brake pedal gives me some pressure as if its working. However, as soon as I turn my car on all the pressure in the brake pedal goes away and I can push the pedal to the floor with barely any friction. After I pump my brakes with the brake fluid cap off while the car is off, the pressure slowly returns and I get the stiffness in the pedal again as if the brakes were fine. But again, as soon as I turn my car on the pressure leaves and the brake pedal can be pushed to the floor very easily.

Any idea/suggestions here?

 

i think it wasnt bled properly, and i would check for a vacuum leak in the brake booster

the stiff pedal is when the booster used up all its vacuum or its vacuum leaked, as soon as u start the car you apply manifoldm vacuum to the booster allowing it to function

this would lower the height of the pedal but not just its stiffness
since the pedal goes all the way to the floor i would bleed the system again

 

we've bled the system again, we're going to try it another time however and start with the master cylinder and go all the way down because we've tried everything else when it comes to bleeding

how would i check for a vaccuum leak in the power brake booster? and is there any other things we should check for that could be the cause of the problem?