Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Description And Operation: Description
Variable Intake manifold Solenoid (VIS) valves are installed on the intake manifold (VIS Valve 1) and the surge tank (VIS Valve 2). VIS valves 1 and 2 control vacuum modulators that activate valves in the intake manifold and the surge tank. These valves are opened or closed by ECM according to engine condition (Refer to below table).
| Engine condition | VIS valve 1 | VIS valve 2 | Operation |
|---|---|---|---|
| Intake Manifold | Surge Tank | ||
| Low speed | Closed | Closed | Increasing engine performance in low engine speed by reducing intake interference among cylinders |
| Medium speed | Open or Closed | Open | Increasing intake efficiency |
| High speed | Open | Open | Minimizing intake resistance by shortening intake manifold length and increasing area of air entrance |
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.