Indicated MPG

[Cadman]

My new 09 Ford Focus Couple has a MPG readout that gives a real time average of the mile per gallon. So far after 4 tanks, it is consistently at least 2 mpgs higher than what I actually get. Does anyone know what the parameters are that are monitored to calculate this? Obviously Ford is dividing the miles driven by something. Is it just using the fuel gauge reading, the fuel pump amps, injectors, TPS, or some thing else.

I am very meticulous about tracking my mileage and try to fill up at the same pump and cut off the fuel at the same point. I then average my numbers and compare them to the readings the car indicates.

[phantom_smack]

They dont actually tell us how it works but I would guess it uses the sending unit reading plus app sensor and maf sensor.Ford tells us mpg and dte are just approximate and nothing should be changed if its a little off.

[chukarhunt]

Sounds to me like it is just advertising. For the average consumer they probably don't check the mileage, they just look at the readout. Ford may have overcompensated to make themselves look good, you never know.