OK, it's still mpg related, something weird with the MFD.
After filling up with Esso Supreme last night and driving literally a mile home with around 35mpg displayed "since fill" when I got home, and today we went to the Metrocentre and back (16 miles each way).
On the way there, the car's mpg progress along the journey seemed to lag significantly behind that expected with my Shell fill up. Getting onto the dual carriageway, i'm usually up to about 22mpg and it was around 19mpg. As the miles rolled on in the journey, the car seemed to be around 3mpg behind expectations at every point (for the first half of the journey, which is the same route as my commute). When we got there, the car was reading 26.2mpg for the journey - the journey is a little longer than my commute, so I expected slightly better than the 29mpg i'd been getting on the commute.
I did wonder whether a change in fuel brand on the fill-up had prompted the car making tweaks to "learn" the best setting tweaks for that fuel (I found a similar thing happened with the GTD when switching between Esso and BP), and maybe it would take 20 or 30 miles to learn to make the most of what it had.
Anyway, we were in the Metrocentre a good 4 hours (watched the new Mad Max film and did a bit of shopping), so all the journey data will have been reset when I jumped back in the car. Drove home and the car said it did 28.8mpg for the trip.
So what did the "since refuel" mpg read? 29.1mpg. By my calculations, 1.5 miles @35mpg + 16 miles @ 26.2mpg + 16 miles @28.8mpg = a total mpg over the 33.5 miles since fill to be 27.7mpg.
The way the range read (340 miles left after 33.5 miles done in since fill) correlates with early indications given by the car for my first tank (Shell V-power) of around 370 miles for the tank.
The range and "since fill" mpg seem to tally at around an indicated 29mpg, slightly at odds with the "since start" mpg readings for each of the 3 independent trips.
Definitely overthinking it here, but that's because i'm trying to establish whether Esso is noticeably better or worse than Shell for the R. Today the car seemed a little less lively with Esso than it had been with Shell (again it could be that "learning process" with a change in fuel).
