Karl PLEASE don't buy or install any HHO unit made from Glass Jars/Bottles. Mine was made from stainless steel in a factory. It has helped a bit, nothing like the Groove.
Sorry the Mistifyer didn't work for you, I wish I'd never mentioned it now. Think I'm gonna send mine back. Von the Inventor is a Really pleasant chap, maybe it does OK on big engines, I dunno. I inly tried it because of my advanced ignition system. If I go back to anything else ingesting water it needs to be more like humidity not water. I need to ask him if it needs further adjustments.
Sorry your ride still has issues. Yes you need a vacuum guage, and a vacuum pump is a good tool as well. Might look for a used TB at a boneyard, bolt it in, if it runs OK, you could take Ron up on his offer.
I'm Very Adventurous w/ car stuff, I look at new/fringe stuff a lot. Some cars are just frustrating and stubborn w/ the Groove. If it's digging in it's heels and won't budge, then you're still in diagnostics Land. Maybe the Intake Gaskets are leaking, something still is not right.
Throwing gizmo's at an engine hoping for miracle results does not usually work (ask Me how I know). It takes good sound science for results.
The Groove does/can work. but it's like Dance Lessons--not much good with a sprained ankle.
Don't mean to be un-kind w/ this, but truth is truth.
Investigate, analyze then act.
Tracy G