Originally Posted by LotI
You are more than welcome to run premium when unnecessary. Thanks for stimulating the economy.
In my TGDI I run E15 and smile while saving enough for a free tankful every couple months
Common thought is that ethanol in the fuel actually burns cleaner and dissolves deposits.
Oh and from someone who ran a study with data, which people here demand.
E0. I have a decade plus of accurate mpg records for 5 cars comparing ethanol-free gasoline(E0) to E10. Adding just 10% ethanol to E0(E10) collapses mpg by 8%, 8%, 7%-8%, 7%, & 5%. Ethanol burns efficiently in high 114 octane, high compression ratio(16:1) ETHANOL engines. Used(not burned efficiently) in low 87 octane, low compression ratio(9:1 to 11:1) GASOLINE engines, ethanol fails. Not just old cars either. My two 2013 & 2016 Elantras (bad-mouthed for poor mpg & re-assigned.. EPA--40 to 38), average 39+mpg with E0 & easy 14% city driving, or 38mpg with 21% city & very heavy stop & go traffic. Both cars collapse mpg by 8% & 7%-8%, when using(not burning efficiently) E10. A 2007 Dodge Caliber lost 7%, when using(not burning efficiently) E10.
Here's the rules: Diesel engine engineers know how to build diesel engines burning 100% diesel fuel for efficiency. Ethanol engine engineers know how to build ethanol engines burning 100% ethanol fuel for efficiency. Gasoline engine engineers know how to build gasoline engines burning 100% gasoline(E0) for efficiency. Mixing fuels, for which the engineers do NOT design their specific engines, means mpg losses, well in excess of the btu content differences between fuels.