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question where can I connect a gauge up to check?

As close to the center of the intake manifold as possible. On the EJ engines, that usually means a connection just to the front of the throttle body. Be sure to use a "T" so that whatever was connected there still gets vacuum while the gauge is connected.

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i have't got to this yet since a death in the family but I'm pretty sure a gasket is gone on the inake manafold that mates to the engine.. don't hear it at idle but if you hold it around 2K you hear this air.. But my PS pump is also leaking but I doubt I'd have that hiss.

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I just came from outside.. my hose is a little too big in the I/D but I took the hose off on the L shaped vacuum hose just after the T/B and I got no reading until I revved the engine.. if I did the hose where the FPR was I got a good reading.

 

 

Maybe I used the wrong location?

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I just came from outside.. my hose is a little too big in the I/D but I took the hose off on the L shaped vacuum hose just after the T/B and I got no reading until I revved the engine.. if I did the hose where the FPR was I got a good reading.

 

 

Maybe I used the wrong location?

You obviously first connected to a source of ported vacuum. What you want is a connection on the intake manifold, to the front of the TB.

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Looks like I should do the spark plug test instead? The pvc should work too right? I think mine is due for a replacement soon

I thought we were discussing the connection of a vacuum gauge. If there's more that this is related to, you'll need to be specific.

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Using the PCV connection isn't practical, hence the ";)".

 

As we've discussed, the best place to measure vacuum is at a central location on the intake manifold. Sometimes that isn't a choice. Since the FPR needs to know how "all cylinders" are doing, even if the point isn't ideal, it's adequate for your needs.

 

The main difference the vacuum take-off point on the intake manifold will make in the measurement is that a central point tends to average it better -- that is, there's less pulsation. If you see more needle vibration than you'd like, you can dampen the movement by restricting the flow. That can be done with an orifice in the gauge's vacuum line, or something as simple as pinching the hose. Just be sure the needle movement isn't indicating an actual problem before you damp it out.

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