[T77911S]

you can also remove the vacuum hose on the side of the intake. pull a vacuum on it and see if it holds.
this is a GREAT test because it also tests the hose or vacuum leaks

you can buy a hand pump for about $30-40 at HF.

I always thought the brake pedal got hard when the booster did not work.


I was not happy with my 930 brakes when I got my car. I thought my 77s was much better.
brake fade was bad, poor stopping power.

low pedal could be air in the lines which means bleeding. -start here,. I would do a gravity bleed.
open the nipples and just let them drain.
you could also have pistons that are sticking in the calipers,
bad master cylinder

I had issues with the calipers. in the end I ended up putting grease on the inside seals so the pistons would all pop out at the same time.
if you remove a caliper, put a 2x4 in place where the rotor goes. apply compressed air, does not take much if they work properly, and all 4 should pop out at the same time.

I used cool carbon this time.