Inconsistent range

[Robs317]

Last two fills on my Audi s3 has had my range being quite a bit down vs normal

my petrol light didn’t come on until I hit 20 miles on the range counter when normally it goes on at 30

30.00 in fuel I’m general gets me 210miles plus on my range counter. However it only went to 170 on my last fill up and I’m not sure if I’m being paranoid but I feel as though it’s dropping faster and the car is less economic, with lots of attention I’m struggling to get 25mpg driving round town in eco driving very steady.

What potential issue could this be down to ? Are there sensors that I could get checked ?

 

[Neil C]

I have also experienced a drop in MPG over normal in my TDi. Thought it may have been a batch of poor fuel, so pushed the boat out and went non-supermarket. Made little or no differece though.
Low and behold, as soon as the cold snap ended my MPG is back to normal.
Hopefully you will notice the same thing.

 

[Robs317]

I have also experienced a drop in MPG over normal in my TDi. Thought it may have been a batch of poor fuel, so pushed the boat out and went non-supermarket. Made little or no differece though.
Low and behold, as soon as the cold snap ended my MPG is back to normal.
Hopefully you will notice the same thing.

Didn’t think of that thanks

 

[AlS3BE]

My s3 does about 270-300 per tank regardless of weather. Does better in long distances and had 400+.
My old diesel in the winter was worse and this is down to cold weather and winter diesel which has more additives to stop it freezing.

 

[JohnM100]

Estimated range will always be lower in cold weather.

The car uses a calculation of fuel burnt over the last ~30-50 miles to project range based upon what is still in the tank. Assuming lockdown and shorter journeys this is not surprising, aside from how heavy your right foot is.

 

[Damo S]

My car hasn't been great on fuel recently either. Shorter jounerys and being a bit heavier footed but its also a lot to do with the drop in temp which affects the car in 2 ways:
1) It takes a fair bit longer to get to proper running temperature (oil temp is up at 80 degrees plus)
2) Colder air is more dense so wind resistance is greater at any given speed.

Number 2 is pretty significant but I couldn't tell you by how much.