Vacuum Brake Boosters are still the most common brake boosted in use. They use engine vacuum to assist you in apply your brakes. The vacuum booster multiplies the force applied to brake to pedal, resulting in less effort being required to apply the brakes.
Electric brake boosters accomplish the same thing as vacuum brake booster, just in a different way. They utilize sensors and electric motor.
Hydro-boost brake booster use the power steering pump to accomplish its job.
Signs of a bad brake booster:
- Hard brake pedal
- A hissing or whistling noise, usually when the brake pedal is pressed.
- Increased stopping distance
- Leaking fluid (Hydro-boost)
- Illuminated Warning Light (Electric brake booster)