After some research in the forum I get the idea.... I have to add some extra wight (my own + diesel), will try today

Have new question: Torque tells me "icy conditions", but can't show ambient temp... can this be fixed?

For correct MPG / KPL you may find you also have to play with the MPG "trim adjustment" found in the vehicle profile settings. After numerous test drives to collect data I finally have mine set at 0.835 for one car and 0.945 on another to get the figures to be very close to the onboard figures diplayed on the dash - which I know is pretty accurate. It takes at least 10 miles of averaging for the numbers to start to settle down.

At least this is what I have had to do. The default settings had my off by over 5 MPG.

So how is this trim number determined? My actual calculation and the Torque Display are way off. Is it a matter of dividing the calculation (done by hand) by the number given by the app? I got 12.5MPG by hand the other day, but TORQUE consistantly has me in the high 20s.

I'm just a user, not a developer but I had to play with the trim number for about 10 drives over the same route (my 35 mile commute - mix of highway and secondary roads) to be able to tweak the number so it was reasonably accurate. But even after all the tweaking sometimes at the end of my drive it reads 1 MPG high and other times 1 MPG low (against the cars internal trip MPG figure) even with the same trim multiplier. My experience was even minor changes to the trim number have a quite noticiable effect on the average. I had to go down to two decimal places. I settled on 0.84 becuase 0.83 would read consistantly low and .85 would be high.

Hi!

In the latest versions, there is an 'Enhanced MPG Calculation' in the OBD2 adapter settings that you can enable that can increase the accuracy of the MPG calculation (it polls more sensors to bring the accuracy up), so you may find an improvement with this.

It's very important that the engine size/displacement, and fuel type in the vehicle profile is set correctly for an accurate MPG figure on some vehicles - if it's left at it's default of 1.6 (and you have a 2.0 litre engine for example) your readings will be off

Also make sure you have the correct units selected in the settings. If you are in the US you may want to enable US Gallons, if you are in europe, you may want to disable US gallons (as Imperial Gallons and US Gallons are quite different amounts and can give rise to different readings)

I find the enhanced mpg even more off than the regular mpg. And it varies wildly. Do you use cell phone location for that? If so, and you have GPS off but location by cell tower on, the location can vary a lot. Could this account for it?

Hi!

The enhanced MPG would have been more off than the regular MPG calc due to an old bug that was fixed in the version released today, that incorrectly converted US/Imperial gallons in the wrong direction - it should be considerably better now that has been fixed (make sure you specify the correct units (US/Imperial) in the settings as that will also affect the output of the display

GPS / cell positioning isn't part of the MPG calculation at all - it is entirely OBD2 based on information from the vehicle ECU