Fuel computer under reading

[duckson]

Just filled up and had done 372 miles since the last brimming of the tank, this time i put in 48 litres. By my calculation this is 35mpg, yet the onboard fuel computer was stating 31mpg. Is it usually this far out?

 

[Willis]

I've noticed mine does seem to read around 2-3MPG low from what I work it out at.

I just leave it on the ''Fuel Used'' display and don't worry about the MPG.

 

[MarkCup]

I've found this. Without fail every single time I fill up, the calculated figure is better than the displayed figure by 2 to 3 mpg.

I thknk it's Renault erring on the side of caution. When I had my 172 Cup id did exactly the opposite...it overstated the mpg by 2-3.

 

[Ross]

Are you sure? I'm averaging 26mpg and I don't put my foot down at all. I just make 320 miles per tank (all according to the car clocks)

 

[luke3]

Mine also under reads by 2-3mpg!

 

[academic]

mine says 35.1mpg, and when i've calculated it by using the distance and fuel used it should be 35.5mpg i think

 

[Foxspeed]

Just filled up and had done 372 miles since the last brimming of the tank, this time i put in 48 litres. By my calculation this is 35mpg, yet the onboard fuel computer was stating 31mpg. Is it usually this far out?

sounds about right to me

 

[197]

32.4 at the mo. Dont really watch it as I may start self harming

 

[philmots]

Same here. It under reads by 2-3 mpg.

Sitting on 35.2 over the tank at the minute, due a fill up shortly so will see the final figure.