My brakes don't hold the car still unless the pedals all the way to the floor. Booster is unhooked because it doesn't work and I haven't had time to replace it yet. I know I have a leaky wheel cylinder in the front, which I'm replacing both front wheel cylinders. Can I mess anything up by unhook in the booster? It doesn't work at all. With it hooked up there's a huge vacuum leak when I press the brake pedal. Caused the engine to idle poorly and run rich. Brakes have been fine but I'd like to have a more confident brake pedal......any ideas?