Bypass valve testing

Talk and Tech about turbocharged 924/944/968 cars
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notny41
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Inspired by the Slow To Spool thread, I decided to create a new thread on this so as not to hyjack the other one.

I’m wondering if I am testing this correctly. The same thing happens when I put the vacuum on the other large port of the bypass valve. I don’t think anything is moving inside. I just end up with maximum vacuum and it holds it theoretically infinitely.

@Tom you said you tested yours with a mityvac. Did yours do the same thing or is mine malfunctioning at this point?
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#1

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notny41
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Uh, nevermind… Now I see how it is supposed to work.
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Seems like it is working fine. it barely takes any vacuum to get it to open up.

#2

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Tom
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I tested whether the top chamber (the fitting on top that the vacuum line plugs onto) could hold vacuum and move the valve. I can play around with one tomorrow, but see what happens when you pull a vacuum on the vacuum tube port. If you like the taste of grease and oil (and who doesn't) you can blow on the bottom port while you pull a vacuum to see if the valve is opening.

edit: posts crossed sorry

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notny41
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I think mine is working correctly - much thanks!

I feel kinda dumb for my first attempt to test the valve... LOL

And I did blow thru each of the other two openings hahaha - yummy oil taste!

#4

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