Thermo Valve boost leak advice

[Spencan]

I have been chasing boost leaks for a while now. I rebuilt the throttle body (thanks Tom!), replaced some cheap aftermarket Intercooler clamps, and replaced the original ISV hoses.

Now when I pressurize my intake system, I can hear air coming from the thermo valve under the intake. I connected a handheld vacuum pump to the tube that connects to the intake and it holds 18 psi with no leaking. When I connect the pump to the other side of the thermo valve (to the evaporator system side) it does not hold any vacuum. I did this with the engine cold. Do have the lines mixed up or do I need a new thermo valve?

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[Spencan]

I bought a new one and will replace it soon.

[Tom]

Sorry I missed this. As far as I understand, that valve simply opens when hot to let evap vapors flow to the brass tube on the throttle body. What were you trying to draw a vacuum on? One the little bunny ear ports?

[Spencan]

Yes, during my research on how to test it, I found some information that read that if both sides hold vacuum, then it’s working properly. One side does but the other side doesn’t.