Originally Posted by suss6052
Not really, it just means your previous mileage was not very good so the computer is predicting that you can't go as far.
The distance to empty seems to be calculated based on a running average of the vehicles mileage for that tank. At the beginning it starts off with the data from the previous tank and starts to adjust down from there until the vehicle is driven more. 310 /12.4 gallons is 25 mpg, 270 is 21.77 mpg. Both are quite low, but if you do a lot of stop and go driving and drive even moderately aggressively that would explain the low figures.
Unless there is also something mechanically wrong with the car.
But the only things that may affect the mileage that severely without making the car drive like crap are things like the tires air pressure.
i do alot of stop and go. I drive mainly residential roads when driving from home to work and back. Probably hit about 10-13 stop signs on the way.
and my avg mpg is 26.4