I was kinda wonderin, because I have the AEM UEGO and it's a piece of junk. If you have the same one I have, the output mode changes at random times, switching it from 0-5V output to MS to 0-1V, effectively trickin MS into thinking it's runnin super rich and MS leans it way out to correct it. My voltage output, even in the correct mode, still doesn't match AFR between the gauge and MS, as 14.7 reading on the gauge will have to be input around 15.8 or so on me AFR tables to keep it correct. Just some thought.