Variable Intake Solenoid (VIS) Valve: Description

Variable Intake manifold Solenoid (VIS) valves are installed on surge tank (VIS Valve #1) and intake manifold (VIS Valve #2). These VIS valve #1 and #2 control vacuum modulators which activate valves in surge tank and intake manifold. These valves are opened or closed by ECM according to engine condition (Refer to below table).

OPERATION CHART

Engine Condition	VIS Valve #1 (Surge Tank)	VIS Valve #2 (In-manifold)	Operation
Low Speed	Closed	Closed	Increasing engine performance in low engine speed by reducing intake interference among cylinders
Medium Speed	Open	Open or closed	Increasing intake efficiency
High Speed	Open	Open	Minimizing intake resistance by shortening intake manifold length and increasing area of air entrance

Fig 1: Identifying Intake Manifold Solenoid Valves

Courtesy of HYUNDAI MOTOR CO.

Fig 2: Identifying Intake Manifold Solenoid Valves Open And Closed

Courtesy of HYUNDAI MOTOR CO.