Has anyone tried to add some kind of smoker/fogger to the line of a "Mag" machine type leak tester to find where leaks are specifically? This is analogous to automotive EVAP leak testers. Using one of those e-cigarette "mods" might be convenient. I've heard that techs have blown cigarette smoke in a plugged sax to look for leaks. Is it used much? Is it effective? If not what are the issues? Thanks.