Winter blend of gas and mpg drop

[camaroman101]

has winter grade gasoline started being used in IL? just noticed a 1mpg drop from in my mpg and was wondering if that could be it. What kind of drop do you guys see in cold winter weather?

[RobertISaar]

with the temperatures the area has been seeing lately, it wouldn't be surprising.

[ksa8907]

yes, i believe the switch was made in late september, but it may take a few weeks for all the summer gas to be cycled out. i wish i only saw a 1mpg hit, im struggling to keep it only a 3mpg drop.

[Gealii]

Ive seen a 2 mpg drop so far best part about this is you do more ecomods so it doesn't drop

[Arragonis]

Anyone from Europe know if this is the case - Piwoslaw or Euromodder ? My current tank is a complate failure at -4-5 MPG on each trip and each "bar" on the fuel gauge going about 10-15 miles earlier than before - that little HM badge below will be going soon

Another factor though is that the weather is much colder - hard frosts now but no snow yet. Lots of rain. I've taken to parking under the car port and pushing the Prius back as far as it will go to get them both in.

[radioranger]

Thanks for the info on the winter gas, noticed about a 3 mpg drop, how about warmer intake air, any help there ?

[wungun]

What's the difference between winter and summer gas?

[RobertISaar]

slightly different composition.

winter fuel is made so that it will more easily turn into a gas(evaporate easier) in colder temperatures. unfortunately, the way they make it do so is by adding chemicals that reduce the amount of energy by volume, so you'll see a hit in MPG from that alone.

[drainoil]

Originally Posted by wungun

What's the difference between winter and summer gas?

Dont some areas of the country also have increased percentage of ethanol during winter?

I got noticeable better mpg in my minivan with ethanol free gas.

[RobertISaar]

if they do, it would be the more southern states.... ethanol and cold temps are a bad combo.

IIRC, Alaska has year-round ethanol free fuel because of it.