Purpose, Function
Ensures vacuum required for braking force to compensate for the decrease in intake manifold vacuum applied to the power brake unit caused by the retard intake valve closing.
Construction
The vacuum pump is installed to the rear housing.

For smooth vane rotation, a single-vane type vacuum pump has been adopted which is equipped with an engine oil lubrication passage.

Operation
Because the vacuum pump is directly engaged with the exhaust camshaft, the vane in the vacuum pump rotates together with the exhaust camshaft, and the vacuum chamber is expanded and vacuum is generated.

Vacuum generation mechanism

Vacuum Pump Removal/InstallationHeater, Ventilation And Air Conditioning
Abbreviation
AAS
Active Adaptive Shift
ABS
Antilock Brake System
ABDC
After Bottom Dead Center
ACC
Accessories
AFS
Adaptive Front Lighting System
...
Supplemental Restraint System (SRS) Precautions
The front and side supplemental restraint systems (SRS) include up to 6 air bags.
Please verify which kinds of air bags are equipped on your vehicle by locating the
“SRS AIRBAG” location indicators. These indicators are visible in the area where
the air bags are installed.
The air bags ar ...
Power Brake Unit Inspection
NOTE:
The following inspection methods are simple inspection methods to judge the
function of the power brake unit.
If there is any malfunction in the power brake unit, replace the power brake
unit as a single unit.
Without Using SST
Operation inspection
1. With the eng ...