After each time I fill up my tank of gas on my 2001 Honda Civic, I’ve been recording
3 4 bits of information: total cost, miles traveled, and the date. I’ve also recorded which brand of gasoline I used, but that’s not important in this case. I’ve been meaning to post statistics of it and finally got around to it.
I’ve made some pretty charts:
The following I made 2 charts of each because there was some data that really skewed it (my trip down to Mt. Shasta)
Totals of 2006:
Miles Traveled: 7598.8mi
Cost of Gasoline: $743.42
Gallons of Gasoline: 275.065 gallons
I did move farther away from my work (3mi to 10mi) in late July after I purchased my new home. That probably has contributed to the number of miles I drive a day and increased my gasoline mileage a bit as now my car can reach the optimal temperature and condition before arriving at work.
There was also this interesting message in one of the MS newsgroups:
So I used to work for a fuels additive company (Read: makes the stuff that goes in your gas to make them run better) and I asked an expert on fuel economy there. Here is his reply:
Several things could be going on. First the altitude should not make much difference in fuel economy. Cars are now equipped with oxygen sensors in the exhaust that determine if the air fuel mixture is correct. If anything the car may seem to be underpowered a little bit at higher elevations.
Other things that can effect fuel consumption. More stop and go driving like you have in Redmond consumes a lot more gasoline. That is the difference between city and highway mileage the EPA requires to be provided for all cars. Another thing is the Seattle area uses reformulated gasoline (RFG) which is made with ethanol and has a lower energy content. That will cost you about 3% fuel economy compared to gasoline purchased in Texas. California has been using “special” low emissions gasoline for years which would have a little bit lower mileage than Texas, but not as bad as Seattle’s RFG. Another thing that impacts fuel economy is colder weather. It takes cars longer to reach operating temperature so the engine feeds in extra gasoline to make it heat up quicker. EPA requires this to get the catalytic converters up to operating temperature earlier. Also gasoline is refined differently by different refiners and the refineries in Northern Washington might be making gasoline with a lower BTU(energy) content. Letting the vehicle idle consumes a lot of fuel. It is best just to get into the car, start the engine and drive off.
Lastly, the type of engine oil can make a difference. In warmer areas cars use higher viscosity oils so that the do not get to thin when they get hot. That same oil in colder climates stays too thick and can cause the engine to have to work harder to run.
Add it all up and you might see 30% difference in fuel consumption, but most of it would have to come from changes in driving habits.