Afternoon all. I'm having problems with my focus 2.0tdci. For a while now it's been ***** on fuel (400) full tank with a mixture of driving. Then today drove 30 miles down the a30 at 70 mph and the temp gauge was only at 1/4 Mark. And the fuel was going fast.  I used 1/4 tank for 40 miles at 70mph. So not happy  . I have changed the stat and sensor and just had the cam belt and water pump done.  And just been serviced aswell so should be sweet. Is there a secondary stat on these and where can I buy as ford vospers will only sell me the whole oil cooler. 

Could be a ton of things, but if it started with the cam belt change would suggest the timing is out.

If its overfilling badly then the temperature won't be as high as the extra fuel acts as a coolant, that could be timing, MAF, or temp sender or something similar

 

Need to ge the OBD port read to see if there is any clues in the codes stored

Thanks for the reply. It was doing it before the belt change aswell mate. Seems to be a bit sluggish aswell compared to when I first got it

Try looking at your DPF pipes and the intercooler pipe which travels from the top inlet to the bottom DPF tube section.  Mine was doing as you describe, i found a split in the cooler pipe and perished DPF pipes (both the 6mm and 7mm) replaced with fuel hosing and problem solved, power is up more than ever and i got from Mansfield to London and back on half of tank of diesel :)