Nubira SX Hatchback L4-2.0L DOHC D-TEC MFI (1999)
Vacuum Brake Booster: Description and Operation
POWER BOOSTER
The power booster is a single diaphragm, vacuum operated unit. When the service brakes are not applied, there is no power assist because equal
pressure (vacuum) exists on both sides of the power booster diaphragm. When the brakes are applied, vacuum is present on one side of the diaphragm,
and air, at atmospheric pressure, is admitted to the other side. Power assist is provided when there is unequal pressure on opposite sides of the
diaphragm. When the brakes are released, atmospheric pressure is shut off, and the vacuum source creates equal pressure on both sides of the
diaphragm by means of a one-way valve in the power booster.
