Poor economy on a Santa Fe

I own a Santa Fe auto diesel 2011.

Despite almost constant use of the ECO button the fuel consumption continues to rise. Originally it achieved 39mpg and now some 28,000km later it has risen to 27.1mpg.

Normal use is a round trip of 40km with every other week a motorway run at sppeed of about 140kph.

The garage have looked at the vehicle and found nothing out of the ordinary.

Asked on 19 February 2012 by egortheblue

Answered by Honest John
In winter and especially at below zero temperatures the consumption will rise because the engine takes longer to warm up and is on enriched mixture for longer. 140Kmh will hit the consumption hard. You can see on the instant consumption meter. At that sort of speed it will be doing less than 30mpg.
Similar questions
Why do summer and winter mpg figures vary?
I have a Jaguar XE, nearly two years old, which averages around 39mpg on the computer set for long periods. 2000 miles ago I decided to check real mpg by checking fill-ups against mileage and was surprised...
I have an Hyundai Ioniq, which I've run exclusively on Shell fuels for the 5000 miles that I've had it. I was getting 60-62 mpg on the regular stuff, then put a tank of the V-Power in and got 64 mpg. I...
Related models
Relaxed motorway cruising. Comfortable ride. Excellent on very rough tracks. Available with seven seats. Good value. Much improved from 2010 with new 2.2-litre diesel.