[Also see my earlier post]
Without specific data being available from the ECU, it’s not completely straightforward or accurate. However, I think it’s reasonable over time.
I kept a record of the fuel efficiency of the vehicle during most of it’s current life using mineral diesel (using a cheap but pretty basic mobile phone app). All I do is record the odometer reading and amount/cost of fuel bought each time – the aim is to always buy a new tank of fuel just after the fuel warning indicator comes on. That way, you can get a reasonably accurate and consistent measure of fuel used since the last odometer reading.
The general conclusion so far is that I’m getting about 5 ltr/100km (or about 47mpg) combined urban/extra-urban. This doesn’t compare well to the Ford spec of around 67mpg combined! No doubt it’s my driving style… (nothing to do with the ultra-conservative simulated driving style of official testing).
