That damned burp / 1300RPM constant

[Lug1]

So.. after deciding to take a vacuum reading, I found this where I meant to plug in the gauge:

So, I thought - yup, problem solved. After installing a new line, well - nothing changed

Still needed to connect the vacuum gauge, here's how it looks like.
Looks like a leak somewhere, still.

https://www.youtube.com/watch?v=RIArLvKU9GI&feature=youtu.be