My meter only does Vac, but i did manage to measure across ports 2 and 3 on the diagnostic port and these are my findings: Key on, cold 7.5Vac. It's 10 degrees today so getting into closed loop is proving challenging without driving. I did notice with the engine cold and I unplugged the EHA it would stumble a bit and idle down (today). Then upon plugging back in, the idle would go up to about 1200, then would normalize, and finally really low idle <500rpms sounding like it wanted to die. If I gave it throttle input it seemed responsive and fine but would return to that low rubble idle. I'm sort of stuck on the idea of how it was driving perfectly then just decided to do anymore. Thanks for your thoughts so far Frank! I can try to wrangle up a meter that will show me duty cycle if that is needed. I've got a spare EHA from my 126 that seemed to work fine, can swap that over to test.