912iS. To start, have had an intermittent aux fuel pump problem. It would run fine than not. I originally thought it might be a bubble from vapor lock on hot days so i ignored it and it would operate fine. I decided to fix it so i did the whole fuel pump replacement kit retrofit. Testing it, the aux pump still did not work. Tried the main electric feed on the aux pump and the aux pump worked. Measured the voltage on the main pimp feed 12.7 volts as one wound expect. Aux pump feed was 11.7 volts. Hmmmm. Tried aux electric feed on main pump and nothing. Same for other Rotax pumps i have laying around. So the aux pump electric feed appears to be the problem but one would think the 11.7 volts would fire the fuel pump up? It is getting voltage but why is it lower than the main pump feed? Not sure what to check now. Any thoughts? Any body had this problem?