It stinks when you don't have enough information to do proper troubleshooting! A few questions came to mind as I was reading this...the sensors use 10VDC, but only output a max of 30mv? Seems like that leaves lots of room for errors with such a small reference range between pressure and no pressure. And, in the picture where you are taking the current reading, I'm gathering you unpinned the original circuit, and used a jumper into the cavity so your meter was placed inline? And then no reading at all with presence of fuel pressure? This makes me think that either the fuse in the meter was open, or there is more than 1 problem with this unit! At what percentage of RPM is the fuel introduced?