916 Fuel Flow

If have run hundreds of hours with both pumps and hundreds with just one. In all cases the actual burn is more than that reported by the Rotax ECU. Fuel quantity gauges in GA airplanes are notoriously inaccurate. Fuel burned totalizers based on fuel flow can and should be far more accurate. If Rotax is unable or unwilling to correct the issue themselves, they should at least drop their prohibition on avionics companies allowing end users to make adjustments/corrections. Pilots with carbureted Rotax engines can make FF adjustments/corrections via K-factor. Why not allow pilots with iS engines the same ability?

No argument form me Mike.  And it’s hard for me to believe it’s accurate at the factory test stand. Everyone seems to complain about the same percentage of error, between 10 and 13 percent.  I suspect it could be fixed if they decided to.  The suspicious side of me wonders if this has something to do with the claims they have made about fuel burn, and needing a data point the validate that.  My 912iS (in a Bristell) exhibits the same error.  I was hoping at least one person would chime in and let us know theirs is accurate, but I have not seen that on this site.