[dcb]

yah that is about it. With just throttle position and rpm I think it is doable, but one needs to map out fuel flow at various permutations of those parameters to accurately track fuel consumption, and it can change if you change the smoke screw setting (and as the pump wears).

So if you can hook the pumps/injectors up on the bench and point the injector(s) into a beaker, add tps and rpm signal, and take maybe 100 readings (10 throttle positions at 10 rpms) and chart that out to fuel flow, that would be one way. Then build the map into the chip and read the same tps and pump rpm and interpolate the fuel flow and etc.

Another approach discussed is sensing the fuel pulse length (piezo?), and injected quantity is then a function of RPM, pretty much.