id take no notice of them clocks myself don't know why there in there for one says your doing 39 mpg and the other clock tells you your got 78 miles left in range to find 20 miles later a visit to top up just my opinion !!
That's why I ask. Mine reports high 40s on a run and ends up being 41mpg and I drive sssslllloooowww up the gears and rarely above 60/65mph.