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FlexFuel E85

I drive a 2001 Honda Civic LX. There is a gas station not too far that sells Propel FlexFuel E85. It is 85% ethanol and 15% gasoline. Would I be damaging my car if I use this fuel? It claims to burn cleaner.

I’m assuming your '01 is not specifically designed as a flex-fuel vehicle.

Most modern cars are designed to handle 10% ethanol fuel without problems. They employ alcohol-resistant gasket materials that don’t degrade in ethanol. The problem that you would have is mixture ratio. Ethanol requires a richer mixture than gasoline. A modern car such as yours will self-adjust mixture to compensate…to a point. As more ethanol is added to the mix, at SOME point your car will most likely run out of adjustment capacity, and run too lean, triggering a code, and possibly causing drivability issues.

What you COULD do is mix a gallon of E-85 with normal gas, and run a tank through, to see if you Check Engine Light comes on. If not, ramp up the E-85 a gallon at a time until you trigger a code–at which point you know the maximum ethanol concentration your car can tolerate.

However, unless you’re experimentally-minded, I wouldn’t bother. Since ethanol contains less energy per gallon than gas, it’d have to be 25% cheaper (or abouts) to be “break-even.” Also, modern cars are already clean-running, so air-quality gains would be minimal.

Read the owner’s manual. It likely will tell you it can handle up to 10 - 15% ethanol. Above that can cause damage.

While in some ways it does burn cleaner, it also has less energy so you burn more.  I the US most of it comes from corn and growing and processing the corn is not without pollution problems.  Overall it is generally not a great idea.

I doubt it your car is a Flex Fuel vehicle. It could do damage if it isn’t. Check your owner’s manual.

I too would rather support corn farmers than support OPEC countries, but it isn’t a good idea unless your car is a flex fuel vehicle.

Your car is not a flex fuel vehicle. Do not use E85. Ever.

E85 is just a way for corn growers to make money and their elected representatives to gain re-election. Even if you had a flex fuel vehicle, it would not be economical to use.