The range left is cetainly quite inaccurate and, as mentioned above, aerodrag appears quite different when there is a significant headwind or tailwind. In the FL Octy 2 TSI VRS it only managed 35 mpg in to the SW wind down to Plymouth but 43 mpg coming back at leasurily cruise speeds of just beow the speed limit.

Car's computer showed 425 miles travelled since fill up, zero miles on the "fuel range" but could only get 52 litres in ie fuel computer paints a worse picture, I think, to make you fill up even though there is half a gallon to a gallon more in the tank than it suggests.

Fuel computer showed 520 mile range when fulled up but I doubt I will get much more than 450 miles as it seems over optimistic on the instant and estimated mpg and range by between 5 and 10% when compaed to actual.

Edited 30 December, 201213 yr by lol

Bri a direct comparison for you ( ok I've no map yet and engine is only 900 miles )

I did the same drove up to Scotland yesterday and home today a total of 492 miles mostly all motorway

filled up before I left (reset all the counters) and again when I got home and the calculated mpg is 47.5 for the total trip

On maxidot it showed 48.3 on the way there and 48.0 on the way home

So not so much error with my trip computer as you

Car's only just been serviced and MoT'd, so I can't think there's a fuel leak

I wouldn't guarantee that, had mine serviced by a main dealer and it sprung a leak from the fuel filter housing shortly afterwards. Apparently there's been a few instances of them damaging the housing when changing the seal. Well worth checking as the resultant leak took out the auxiliary belt which jammed the timing and resulted in needing a complete new head!

I've been keeping track of my fuel usage since I'd had the car and reckon the trip computer reads about 5% optimistic on fuel (about 49.5 on the readout but 47 calculated using fuel receipts and indicated mileage). I've not checked the accuracy of the mileage reading but the speedo reads about 5% high compared to the GPS so would assume that's from the an error in mileage reading. That should give an error of nearly 10% real world compared to the trip computer.

Edited 11 January, 201313 yr by RizzoTheRat