your guess is as good as mine, but I would second that. I have read somewhere on Torque forum that diesel support is not complete (but i t was years ago). I assume that MPG calculation is based on engine load, RPMs and injection pulse width and Torque cannot calculate it properly for diesels not having enough data. In my opinion this would be better candidate for trying:
https://play.google.com/store/apps/d...eeo.rtadvanced as it *should* access more data. But I doubt Torque can handle it other than to display.
last "official" answer on official Torque Pro forum i have found is silence. (see:
Forums — » Torque OBD ECU Scanner » Torque Discussion / Ideas » MPG Calculation for Diesel PUTorque)
(BTW: you dashboard looks very similar to mine - and in previous versions of Logan there was instant MPG readout option on that odometer display. But around 2009 they cancelled it "because it was distracting drivers too much - as they told me. Don´t you have one? (I have just average MPG, always 0,3 l/100 km too optimistic.)