Originally Posted By: badtlc
Due to lack of precision, a one-time calculation involving a value from a gas pump isn't very precise. Most onboard readouts are more accurate, especially if the reading is calculated with very few starts such as the OP is describing.
If you are resetting for a long trip, the readout is the way to go and much more consistent, precise and accurate. If you are making a relative comparison, it is the only way to go. Pencil, paper and odometer make for more accurate long term calculations. Gas pump calcs are useless if not at the same pump and even then can be off by as much as 5%.
Well he is going a couple of thousand miles (I don't drive it but according to Google maps its around 1000 miles each way) so it would be a few gas tanks (like 5 if he goes 400 miles per tank) but then the following is posted;
Originally Posted By: tig1
I think it is more accurate to hand figure the MPG over 5-7 tank fulls not just one. However when I go the Gainesville I only require 2 tanks of gas.
HUH? Is it not around 2,000 miles RT? How big is a tank in a Fusion?
I still stick with my comment on pen and paper. This data is over more than a single tank so if the pump clicks off a gallon or two early at the end its not going to fudge the numbers much.
Take care, Bill