I hope Tracy comes back soon. My EM2 is behaving very strangely. TAS 160 when stopped,  OAT -57, MPH 1800, H20 287, oil 120, all with engine not running.  

John;

Grounding is an issue, but I’m sure you have that handled.  Another issue is the distance from the display to the AQM.  I followed Tracy’s advice and put the AQM close to the engine; you know, in the back where it belongs.  I extended the wiring to the display to about 9’.  Tracy wasn’t sure, but thought it may be an issue, introducing noise or whatever.  He added a filter to my EM2 board.

Al