Causes and fixes when a brake pedal sinks suddenly all the way to the floor.

Posible Causes
Low on Brake Fluid
Possible Brake Fluid Leak
Air in the Brake Lines
Failed Brake Booster
Failed master cylinder

How To Test the Brake Booster
1. Pump brake with engine off.
2. Hold the brake pedal and start the engine.
3. The brake pedal should move forward toward floor.

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