Cm6017 said:
Forgot to mention; I have been sticking religiously to using the efficiency programme and cruise control but this appears to make no difference.
I don't find the efficiency program that much efficient, and the cruise control can actually get you to spend more fuel.
What makes you spend more or less fuel is pressing the accelerator more or less. If the cruise control is turned on, you are forcing the engine to accelerate while climbing to maintain speed, thus spending more fuel. With the cruise control off, what happens if driving economically is that you lose speed while climbing, exactly because you don't want to press the accelerator.
Regarding the gear change indicator, I actually don't think it helps either. Maybe theoretically that's the spot where you should change gear, considering all the variants in that instant, but what if those variants are about to change? The computer can't see what comes ahead, only you can. So it tells you to change from 4th to 5th gear right before you start climbing that hill, or right before you get to that truck and need to overtake it, but should you make that change? I don't think so, as you'll need the power just a few seconds later, and if you're in 5th gear you will have to press the accelerator a bit harder, thus spending more fuel. I see it merely as an indicator.
What I try to do is always be in the highest gear possible that allows me to have the engine running around 2000 rpm while pressing the least possible the pedal.
My total average is around 47 mpg, with no economic concerns.
In those journeys I do try to save some fuel I can get to 56mpg, and I've even done a 15mn journey that ended with a brilliant 68 mpg average.
Also I find the instantaneous mpg info on the DIS to be very useful if you want to understand what makes you spend more or less.