Now it is running at roughly 29 mpg on the display & just under 29 using mileage & fuel added . A one off check of distance from google vs the odo shows c 4% under reading. Can't say I am bothered about that.
The speedo error & the crap fuel gauge is more annoying.
I have the same issue with the fuel gauge John, it never goes above a 3/4 reading and it runs low way earlier than is accurate. I am yet to fill up and put 30L or more in the tank.
I am currently trying to rely on resetting the trip counter when I refuel but still not brave enough to run for too long as the dial drops.
It is an annoyance but with all of the other madness in the world, I'm learning to live with it.