No, in many cases those "one tank wonders" are not valid and should be ignored. I find, looking at sites like fueleconomy.gov, that many people will post stellar mileage early in their cars' lives and not continue to report honestly as fuel economy normalizes. For example, one 2007 Nissan Versa owner reported one tank at the end of 2006 at 36.6 miles per gallon and then he disappeared. Was his mileage mis-reported and he failed to report the 25 mpg he probably got on tank #2 or was he a plant from Nissan? We'll never know, but knowing that date gives us a good reason to ignore that figure.
Comparing to similar cars that are still being reported is very useful as our cars age and things gradually change.
__________________
2008 Toyota Prius Touring purchased 04/2016 at 101k miles, currently at 186k miles
2009 Acura MDX purchased 12/2019 at 159k miles, currently at 194k miles
|