I did this for a couple of weeks/months in my old Zetec Collection (identical mechanical spec to yours) and I got 465 miles from my tank.

Actually 2,500 rpm is the most economical engine speed not 2,000
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2011 Focus 3-door Zetec 1.6 TDCi.
Previous <img src="/images/graemlins/stemo.gif" alt="" />s - 2006 Panther Black & 2007 Red. Gone and quite forgotten <img src="/images/graemlins/lol.gif" alt="" />