Afternoon all,

I've literally just picked up my 2012 1.6 TDCi S Max and driven it 50 miles after putting £100 of diesel in - that's 52.66 litres or 11.54 gallons from the receipt. 

The 'miles until empty' on the computer states 299 and goes up in single mile increments as I'm driving. Now, I'm not a Formula One driver so not lead footed at all - in fact, I achieved 57.1 mpg on the way home up the M1 but at this rate the car will allegedly do 25 miles to the gallon.

I'm sure that there's more than 299 miles for £100 worth of Diesel or am I deluded? I'll assume that these things have a habit of working themselves out...

Any ideas or just putting me back in my box would be appreciated!

Thank you,

Mark.

The computer is good but it can't predict the future otherwise I'd ask it to pick the lottery numbers 🤣

It bases the calculation on the way the vehicle has been driven and on what type of motoring has been done in the last 'rolling' 500 miles total.

If the previous driver had a heavy right foot and did a lot of stop - start driving around town then the computer takes it's best guess at how many miles it expects to get from a tank full of fuel. Now if the driving style changes and the type of motoring changes the computer will work this out over the next few hundred miles and make adjustments to the expected range. At the end of the day it is not an exact science, just ask the pilot of any Airbus and they will tell you the fuel computer is only a guide.

Thanks very much Unofix, that helps no end. I was confused as to how it worked it out so you've explained it in terms I understand! 

Mark.

7 hours ago, unofix said:

... just ask the pilot of any Airbus and they will tell you the fuel computer is only a guide.

Aahhh, another fan of, 'Air Crash Investigation'! Absolutely correct though. For decades I have simply done my own MPG test, fill to the brim (ignore all advice not to!), and use my reset zero'd odometer to tell me how far I have left. Of course, the bright flashing red low level fuel LED is also a bit of a giveaway.