Questions about Bosch bypass valve

I installed a fmic a few weeks ago and took on one long test drive. Noticing the trailer hitching was worse and researched doing a bypass valve.
I havnt driven it since, been waiting on getting a new radiator.
I had a Bosch bypass valve I bought about 10 years ago from forced four. So I bought the needed hoses and started plumbing it in.
I have it on the throttle body side and hooked up. But I have it unhooked from the Turbo inlet. And the inlet hose to the Turbo is block off.
I had to move the car out of the garage yesterday and it wouldn't stay running.
The valve is "bypassing" at idle so I have an unmetered air leak right now. I unhooked the vac line to the bypass valve and was able to move it.
Question is: is this normal? It bypasses at idle, or high vacuum conditions?

No idea on the style of BPV you own. I had a DSM BPV on my car around 8 years ago, it had trouble idling and running while I had the valve installed.

the vac signal at idle is normally enough to open the bosch or dsm bpv. if you have it vented and are still running the VAM, it needs a check valve on the dump to atmosphere.

if you link it so its venting back in front of the turbo, then you dont need the check valve & you shouldnt have any issues.

thought this was old news by now fellas! lol