Fig. 2.57. VAD system of Mazda 6 with L3 engine: 1 – VAD system valve; 2 – VAD system control solenoid valve; 3 – vacuum chamber of the VAD system; 4 – VAD system check valve
The VAD control system opens a flap in the air cleaner housing at high engine speeds to increase air flow. The system consists of a flap, a control solenoid valve, a vacuum chamber, and a check valve. Typically, a spring-loaded rod opens the flap (Fig. 2.57).