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Gas quality and mpg

We moved from Oregon to Alaska a year ago. Since we’ve been here our vehicle mpg has decreased substantially. My husband’s 2001 Ford Ranger went from 21 to 14 mpg, and my 1996 Honda Civic from 32 to 22 mpg. Yes, it’s colder than Oregon in the winter, but we’re experiencing this year-round, with regular maintenance, similar driving speeds, good tire pressure, garage and block heaters. What gives? I’m thinking it may be the fault of the gas production here. Could this be?

How does the percentage of ethanol in Oregon gasoline compare with the ethanol content of Alaskan gasoline?

While I suspect that the ethanol content is actually lower in Alaska (and thus can be excluded as a negative factor), this is one issue that needs to be addressed.

If gas is being formulated different for Alaska, which it may be, a search of the gas company sites, perhaps the American Petroleum Institute (API) site, or perhaps a simple Google of “gsa formulations in Alaska” might answer your question.

How about other driving conditions?  Length of trips, hills stop and go etc.  Every time you hit the brake, you are wasting fuel.

I would want to ask about the hills up there but the hills in Oregon should be steep too. What’s the altitude in your area? How are the roads, paved or loose gravel? They might be getting away with Winter fuel all year long too.

Thanks, I’ve found no one who will admit to adding ethanol to the gas there.

I think this is the correct answer…

Here in the northern continental US there’s two types of formulated gas…One for winter…one for summer. There’s a noticeable decrease in gas mileage using the Winter formula. I suspect that Alaska uses the winter formula all year round.

Albany to Corvallis, where we drove, is all pretty flat. Anchorage has some rises and falls, but not what I would call hills from where we live to where we work. The roads now are snowy and there is gravel for friction, but summer the conditions were comparable. Altitude: 144’ in Anch, 230’ in Corvallis. The winter fuel idea is definitely something to find out about. I’ll look into it. Thanks everyone for feedback!

Alaska has MUCH lower average temperature. Operating a vehicle in your conditions produces poor fuel mileage, it’s a simple as that. When you buy gasoline, you are buying BTU’s. THAT’S what powers your car, heat. The “quality” of your gasoline is the same as everyone else’s…

Yes, actually, that was my first thought; however, my car came first from North Dakota, where the winter averaged -30 to -10. It neither lost nor gained mpg when I moved first to Arkansas then to Oregon. But here in Anchorage is where the problem first occured. And even this 2008 summer with temps 50-70 degrees. I noticed little change when the temp here went from a high of 70 to a low of -10.

then maybe have the temp sensor tested or replaced (usually at botm of radiator) as it help decide the actual engine temp and sends signals to computer to adjust accordingly…this is often overlooked…your thermostat is probably ok.