[richardstubbs]

Now, here's an odd thing - the average fuel consumption on the display always settles out at about 37mpg or so. But I've calculated the real mpg on 3 consecutive tanks of diesel and it's been 47, 44 & 46 mpg. Yes, I can do sums, so what's going on?

 

[baxter2308]

Now, here's an odd thing - the average fuel consumption on the display always settles out at about 37mpg or so. But I've calculated the real mpg on 3 consecutive tanks of diesel and it's been 47, 44 & 46 mpg. Yes, I can do sums, so what's going on?

Same here, I do quite a bit of city driving and know I'm getting 40-42mpg but the trip computer says I'm struggling for 37mpg. Other AO's say that their trip's are pretty much bob-on though, my 147 has had MAF/EGR problems which affected fuel economy. Repairing them solved the economy issues but not the trip computer's figures so maybe a simple ECU reset will solve it. Hope you get it sorted.

http://www.alfaowner.com/Forum/alfa-147-156-and-gt/201163-ecu-reset-its-a-miracle-cure.html

:thumbs:

 

[Spacecadet]

My car says it gets 24 mpg, it's closer to 19.

 

[Chris M]

Mine says 23 and I'm too worried to work the real figure properly

Seriously, I didn't buy a V6 to worry about fuel consumption, I just fill it up when it's empty - again!

 

[richardstubbs]

I am worried about the fuel consumption, that's why I bought a diesel

Glad to hear it's not just me. I don't mind really - if I wanted an accurate fuel consumption display I'd buy an Audi. I want a car that's fun and rewarding to drive on a daily basis, that's why I've had five Alfas.

I'm just fascinated as to how it can take basically the same data and come up with a different figure! If the fuel pressure was low maybe? But it goes like stink and FiatEcuScan says everything's fine. So no problem at all really.

 

[Spacecadet]

I think it all depends on the way the car calculates. My ford average fuel consumption thing goes down when the car is stationary, the Alfa doesn't. It doesn't appear to count time at idle.

Say I reset the average at the petrol station, then I pull away to the junction, the display in my CMax will show about 20mpg because I've moved about 40yards in 1st or second gear. Then at the junction, if I get stuck there, it goes down quite fast. The car is using fuel, but I am not moving. Can get down to 10 ish.

My Alfa just stops changing when I stop.

Also, my Ford will show an instant mpg of 99.9mpg (3digit display)?when off throttle say coming towards slower traffic on a motorway, or losing speed for a turn off. The Alfa doesn't change much, (slowly easing up to 40mpg or so, however, all modern management systems cut the fuel in these situations so you use none the figure should be the max display able as you are doing miles with out using any gallons.