While driving my 2010 Prius I saw substantial MPG losses due to the Additives in the Northeast. also the Hybrid took somewhat longer to warm up than conventional cars .The fit will suffer as well ,but not quite as bad. Am please with the MPG for my 10 Sport AT yesterday my first trip 32-35 avg. mpg.

 

Welcome to the freakworld! You're right, winter fuel blends will put a dent in the MPG. It's the EPA's way of trying to do something???? Exactly what it is I'm not sure but it does result in all cars burning more fuel in those targeted areas.

K_C_

 

Well, the EPA like all government agencies is not filled with very enlightened, intelligent people. They believe that a Hummer getting 6 mpg at the same pollution level (ppm) as a Honda Fit does not pollute the air anymore than a Honda Fit getting six times the mileage.

 

It isn't just the EPA. It's making fuel that will will properly vaporize but not boil at the different ambient temperatures. Winter blend isn't as energy dense, but is cheaper to make.

The Oil Drum | Refining 101: Winter Gasoline

 

I've always attributed it more just tithe laws of chemistry, fuel/air mix and the colder air

 

malraux - you've found the magic formula. Oil Companies+Govt+EPA Regs = lower production cost = higher profit.

I know it's not that simple and there's a good reason fuel formulation's seasonal change, both environmental and performance wise. It's the new world paradigm that throws me.

Interesting to note that the article was published in 2006. Then came the crash and huge bail-outs and that new world paradigm. I found the comments worth reading and the article well written.