squissing noise when brake pedal is depressed?

That would be a cracked diaphragm in your power brake booster. It should be replaced and the labor should be about $75. Check at advance auto parts for the part cost. A remanufactured one is $97 including the master cylinder, $84 without the master cylinder. And there is a core charge of $15 which you will get back when you return your old parts.

I agree tht it sounds like the power brake booster is wasted. However, I would check the one-way check valve that connects the booster to the engine. If the engine has ever backfired, you may have ruptured the valve.........this could be a $5 fix.

Eather it's as your last answers stated or you need new break pads.

It sounds like the vacuum booster/Power assist isn't working properly. Check for a loose vacuum line from the booster to the Intake manifold. The booster is that Big Black Circle that the master cylinder is mounted to. The Vacuum line should be about the size of your thumb and go from the booster to the rear of the engine. If the vacuum is good then it's probably the booster itself.

yea