Hi high fuel consumption. 

What engine is it and what journeys do you do and in what sort of conditions?

Equates to around 30 miles per Gallon. As DG97 says, you need to give us some more information about the sort of journeys you do e.g. lots of short stop start trips in town/city only a few miles on a cold engine? What sort of weather/terrain are you driving in?  What engine have you got. ? Not sure why Ford are telling you there's nothing wrong electrically it's not the first thing I would associate with fuel consumption issues. 

My 2 month old ST-Line X 140 with about 2300 miles on the clock would be doing about 625 Km on 38L of petrol, that's mainly done on a 70% motorway 64 mile daily commute to work.

 

Full to the gills (42 litres according to Haynes manual), mine will do 550km which is split 95% motorway/5% getting to the motorway.

I think I can drive over 700 km with premium fuel and mostly highway driving. My cars trip computer says 5.0 l/100 km (47 mpg). And when I fill up it says over 700 km left. I've got 15" inch spiked winter tires in my car and tire pressures are 2,6 bar front and 2,4 bar rear. The tires are from good manufacturer. I changed my spark plugs 20 000 km ago and I use a lot of cruise control. Both seem to lower fuel consumption a bit.

Car is 1.0 EB 125bhp Fiesta.

I agree with @DG97 and @Blatto , we need more information about your driving conditions , mainly city or highway ? how much short trips ? your driving style aggressive vs normal ? your engine ? your gearbox ? we need some information to try to shed the light with you on the problem 🙂