I have old thunderbird think early 2000s but maybe before that. When braking have to push then release a little then push and It's hard to push on the brakes. Does it need bled or new vacuum?
Could be a bad vacuum booster, check valve, or vacuum hose to the booster. Usually a hard brake pedal is a lack of proper vacuum. You can test if the booster itself is working propery - with the engine OFF, pump the brake pedal several times. Then on the last pump hold the pedal down. Then start the car, and feel if the brake pedal drops, even if just a little bit. If it did the booster is working okay.
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