1. There is still air in the brake lines. If you did not bleed the brakes correctly, there may still be air bubbles trapped in the lines. This can cause the brake pedal to feel spongy or soft, and the brakes may not work properly.
2. There is a leak in the brake system. If there is a leak in the brake line or one of the brake components, fluid will leak out and the brakes will not work properly.
3. There is a problem with the master cylinder. The master cylinder is the hydraulic part of the brake system, and if it is faulty, the brakes will not work properly.
4. There is a problem with the brake booster. The brake booster is a vacuum pump that helps to apply the brakes, and if it is faulty, the brakes will not work properly.
To diagnose the problem, you should inspect the brake system for leaks. If you find a leak, you will need to repair it. If there is no leak, you should take the car to a mechanic to have the brake system diagnosed.
