fairly accurately. There are numerous ways of arriving at a guesstimate for mpg, but what have you found to be the most reliable method?
I have a mini-computer w/monitor feature on my car that gives various read-outs, it's interesting to see how gasoline usage is being registered under various driving conditions.
I usually just put the nozzle in the tank with the handle positioned in the fast
mode, and when it shuts off - remove the nozzle - and do the calculations necessary to come up with a mpg figure. not necessary totally accurate, but in the ball park.
different temperatures have an effect on volume, which affects the absolute usage.
mho vfe