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.
Idle-Up Vacuum Switching Valve (IVSV) (PRIZM)
The IVSV is located on end of intake manifold on Prizm (below mass airflow sensor on Prizm GSi). The IVSV by-passes air into intake manifold (around the throttle valve of mass airflow sensor on Prizm GSi) when it is activated by the ECM. The IVSV is energized whenever idle speed drops to less than desired RPM due to engine load (i.e. electrical, P/S, A/T in Drive, etc.).
NO RELATED
Use the Manual With the Right Hardware
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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.