Vacuum Leak
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Intermediate
Joined: Mar 2004
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From: Dayton Ohio
Vacuum Leak
2001 C5, 6sp, 23K. I have a whistling noise that develops around 2000 to 2500 RPM which from a hose test ( listening with a piece of hose) appears to be coming from underneath the front of the intake manifold. I know the PVC valve is on the side there and the whistle is not coming from it. Are there any vacuum connections underneath the manifold?
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Joined: Dec 2010
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2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
could be one of the intake port seals leaking... other than that there aren't any vacuum lines directly underneath the intake
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Joined: Jul 2007
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From: Reno is so close to Hell you can see Sparks , State Of Confusion
St. Jude Donor '12-'13-'14
The way we use to look for a vacuum in the old days was to spray a little starting fluid around the motor and when the rpm came up you found your leak.
