Disappearing Coolant

[hhow55]

Not sure about the miityvac, I got mine from harbor freight, works well for me.
In regards to the disappearing coolant, disconnect the Venturi pipe from the intake horn, and see if you find any moisture or coolant. I would then open the flange behind the egr cooler, and check for coolant in the pipe, of course withe the cooing system pressured up would help.
About the @m*m^2, just hit the tab near the top of home page Isx egr delete tab, it's all there to learn.