The gauge can be pretty far out either way, mines only been bang on once or twice so far (I have a whole MPG spreadsheet 
), mine also gets less accurate the longer it's left, or the lower the tank is, but has been no more than 3 out so far I must admit.
I can't get good MPG from it, so I've gone the other way now instead, 80+mph on the motorway and quick pull aways everywhere and.....the MPG is still exactly the same. 55mpg one tank, 56mpg the next and that pattern is constant. Before I moved (extra 10 mile B road every drive) was getting 57mpg one tank and 59 the next. Have only ever seen 60mpg once in almost a year/10k miles.
I couldn't keep under 55 on the dual carriageway admittedly, but was only doing a sat nav 65 on cruise before, and I was doing the coasting, holding momentum, gentle pull aways etc, I was taught to drive economically so have followed that ever since. Used to get over 65mpg on the mapped Golf on a 'run' (50 mile round trip mostly at 75 on cruise) but dropped to around 60 over the whole tank as I was sitting in rush hour traffic 4 times a day every day for college and drove like c*nt the rest of the time...coal and understeer ftw.
I can't believe the DPF would make so much difference, and the weight isn't a huge amount more on the Focus. What sort of rpm are you at in 5th cruising?
), mine also gets less accurate the longer it's left, or the lower the tank is, but has been no more than 3 out so far I must admit. I can't get good MPG from it, so I've gone the other way now instead, 80+mph on the motorway and quick pull aways everywhere and.....the MPG is still exactly the same.
55mpg one tank, 56mpg the next and that pattern is constant. Before I moved (extra 10 mile B road every drive) was getting 57mpg one tank and 59 the next. Have only ever seen 60mpg once in almost a year/10k miles.I couldn't keep under 55 on the dual carriageway admittedly, but was only doing a sat nav 65 on cruise before, and I was doing the coasting, holding momentum, gentle pull aways etc, I was taught to drive economically so have followed that ever since. Used to get over 65mpg on the mapped Golf on a 'run' (50 mile round trip mostly at 75 on cruise) but dropped to around 60 over the whole tank as I was sitting in rush hour traffic 4 times a day every day for college and drove like c*nt the rest of the time...coal and understeer ftw.
I can't believe the DPF would make so much difference, and the weight isn't a huge amount more on the Focus. What sort of rpm are you at in 5th cruising?