Hi,

I have owned a 58 plate 1.4 diesel Fiesta for the last couple of years.

When I have filled the tank previously it has always said the tank will do me 508 miles.

The last few times I have filled it, the computer has said I will only get 454 miles.

I was wondering if anyone else has experienced this or if anyone can suggest why this has happened?

Thanks

Craig

This reading is based on your latest average mpg, so has this dropped?

Colder weather = more fuel used = less miles to a tank?

Boooo Fiesta's should be more like us Northerners, hardy and strong in the winter months, not using extra fuel, should use less, just to show it's winter hardiness.

Pretty sure this comment had no point >_>

When I have filled the tank previously it has always said the tank will do me 508 miles.

The last few times I have filled it, the computer has said I will only get 454 miles.

Yep all the time, I get 550 to a tank, more or less, but everytime I fill up it says around 500 range. Over the course of the next 100 or so miles it usually sorts itself out.

I've also had the range go up on a 10 mile yourney to workl , so it's either correcting or the cars making it's own diesel (I wish) :D

Outside air tempurature has a large influence on mpg figures as I have found. My own very short journey pattern exaggerates this. In the summer I can get 38 mpg, it is struggling to get above 32 mpg now the temperature has dropped. In any case, I don't take the "miles left" reading too literally. Also different pumps have a different cut-off point so you have to fill up at the same station and same pump to be accurate.

Cold air is denser so the car will increase fuel in the mix to allow for the correct ratio for combustion.

If it didn't you would find the power was reduced and have less acceleration.