fuel conumption

[fu94]

I bought my first Audi 3 weeks ago on Friday and I absolutely love it, I haven't drove a car like it in my life and I'm really happy with it, there is a small problem and I'm not sure how to resolve it as I have been searching online with little to no results. I put in enough diesel to get the range up to 300 mile and by the time I got home (at most 6 mile from the filling station) it had already dropped down to 280 miles and then an hour or so later when I drove for roughly ten/fifteen minutes the range had again dropped down to 260 and is now 3 days later sitting at 200 miles left when I haven't done anything close to a hundred miles, I noticed it seems to drop 5 miles from the range ever 2 and a half or 3 miles. I am not sure how to even attempt to solve this as the car is usually in efficiency mode and I try and follow the cars instructions as closely as I can to limit fuel consumption. any help or advice with this problem would be much appreciated as my last resort is to take in to get looked at which I feel no matter what the problem is going to be a costly one.

[Magnet]

Hello Cathal, 

Others more knowledgeable than me will be able to advise with the accuracy of these range computerising on Audis. My experience with non- Audis is that they are guide figures rather than accurate assessments. 

If it were mine, I would fill the tank to the brim, zero the trip and run it over average driving conditions until the gauge reads around a quarter full. Refill to the brim and calculate the average mpg, but I would not be expecting to achieve 'book figures' consumption. 

Kind regards,

Gareth.