I did fill up before the motorway...but when you're doing over a thousand kilometres, your tank does run dry...
As for sat.nav, I somehow managed to disable my iGo app, and google maps only worked for so long - I had issues with data from my phone, which it needs from time to time as well as a GPS signal...but thanks for the sandwich advice, only I'm not sure Brittany Ferries do them, and the 'Hotel' I stayed in was unoccupied - at 20 euros a night, you don't get much service!
Crank shaft pulley is dying? - well, I had best get that seen to asap, if that indeed is the problem
No helpful comment on the fuel consumption? Before I set out on this trip, I was comfortably expecting 50+mpg, but I guess my heavy right foot put paid to that idea. I'm not sure how slow I would have to go to get 50mpg, but whatever it is, it would not make the journey plausible in under 3 days. Extra day in the sunshine = well worth the cost!