Variable Intake
manifold Solenoid (VIS) valve is installed on the intake manifold. The VIS
valve controls the vacuum modulator which activates a valve in the intake
manifold. The ECM opens or closes this valve according to engine condition
(Refer to below table).

Engine
condition
|
VIS
valve
|
Operation
|
Medium
speed
|
Closed
|
Increasing engine
performance in low engine speed by reducing intake interference
among cylinders
|
Low / High
speed
|
Open
|
Minimizing intake
resistance by shortening intake manifold length and increasing
area of air entrance
|
