The brakes on my 87 trans am gta are weak. By weak I mean I have to push all the way to the floor for the car to stop, and still doesn't stop right away. Just bearly! Help!!!

 

How's the fluid level in your brake fluid reservoir?
Sounds to me like you've got a lot of air in your brake lines.
Do you have to apply a LOT of force to the pedal or does it go down quite easily?

 

It goes down about 2 inches and then gets hard I believe it's the master cylinder

 

May still be air, which has to come from somewhere, so yes, the MC may have a defect. Only one way to rule that out: take it apart and look inside
Perhaps the seals have corroded.

 

Thanks for the help really appreciate it

 

Sure. You're welcome. Keep us posted, please!

 

i think i may be having this same problem not sure... i hear like a vacuum noise coming from the brake pedal area and i have to push the pedal down all the way and it wasnt like this before...can burn outs cause this?

 

Bad brake booster if you hear hissing noise. Swapped mine out, now it's fine.

 

It has all the symptoms of a bad brake booster but it holds vacuum so I ruled that out. Now the master is left. Can the master cause a hard pedal after about 2 inches. And the brakes are weak too can't lock the wheels. I ruled air in the lines out because if it had air in lines then the pedal would go to the floor. What can it be. Mind you that I took the proportioning valve out and put a Wilwood one on the rear brakes because I though that was the problem in the first place but still is that same thing