Description & Operation: Description
- 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 |