I drive in also in a similar condition (Southern Ontario, Canada) and
got the average 1 year mileage (Winter+ Summer) as 35mpg (fuel logbook
available at ontariogasprices.com). During Summer mileage was average
40mpg with maximum of 50mpg. I was suspicious, obviously. But that was
a trip from Waterloo to Toronto and back to Waterloo.

What is overfilling, by the way. I fill the tank until the nozle stops
automatically.



On Oct 6, 11:48 pm, High Tech Misfit <m...@privacy.net> wrote:
> mpwilliams wrote:
> >> And yet, my '93 Accord consistently got 10-20% above EPA estimates on the
> >> highway. Go figure.
>
> > This may seem like an asinine question, but what is your process for
> > calculating actual fuel mileage? Also, what is the elevation and range of
> > mean daytime temperatures where you live? I ask the latter because lower
> > elevations and lower mean ambient temperatures, in comparison to the
> > location of the automaker's test facility, will result in comparative
> > mileage improvements, ceteris paribus, due to more dense fuel/air mixtures
> > prior to combustion.I calculate my mileage the old-fashioned way. Start with a full tank (not
> overfilled), drive the trip, fill up again, take note of how much gas I put
> in at the end of the trip and how far I travelled, and do the calculations.
>
> I live in southern Ontario (Canada), where spring and fall temperatures
> range anywhere from 5-15 Celsius (41-59 Fahrenheit) and summer temperatures
> range from 20-30 Celsius (68-86 Fahrenheit). The elevation is somewhat flat
> with moderate hills in places.
>
> EPA rated the '93 Accord automatic at 28mpg on the highway. My car
> consistently averaged 32-34mpg on the highway under normal conditions. In
> fact, it even got 36mpg on one occasion a few years ago. And BTW, those are
> U.S. gallons in my mileage figures, not Imperial gallons.