Gas with 10% Ethanol added

Dumb question, probably, but now am seeing “10% Ethanol Added” at nearly every gas station I pull up to, to gas up. Guy friend told me that even 10% is harmful to cars not “ethanol ready”. Experts please comment. Thanks

Your friend is partially correct. He is probably referring to E85, which is 85% ethanol. Gas with 5-10% ethanol has been on the market for a long time, and your car will be OK. The benefit is a cleaner exhaust, less smog, but you gas mileage will be a little worse; you probably won’t notice. Stay away from E85, because it can eat up some under hood components in older cars.

Not true. Vehicles built since the mid 80’s have hardend fuel systems that can handle a concentration of 10% ethanol in the fuel.

It is true that older vehicles that don’t have hardened fuel systems can be damaged from any concentration of ethanol. But these vehicles fall into the classic/collectable catagory.

But todays vehicle are being designed to handle up 85% ethanol in the fuel. So it’s nothing to worry about. Only that you get less fuel mileage when ethanol is introduced into gasoline.


New Jersey mandates a 10% Ethanol/gas blend year round. Other than a hit on mpg, I haven’t had any problems with my 93 Caprice or my 2000 Blazer. Your Owner’s manual should tell you how much ethanol your car can handle.

Ed B.

So now the gas companies are not only raising prices without justification (remember when they at least used to say “storm in the Gulf limited production” or “Mid East price spike” ) but adding something which give less mpg and requires the consumer to buy MORE GAS? Was this additive a requirement by the gov’t to reduce emissions? Rocketman

Rocketman, I believe the reduced NOX is a desirable side effect. The program is part of an ill-conceived Bush program towards “energy independence”, to back out imported oil.

As you will have read from other posts,converting all our corn and soybeans to fuel will only increase gasoline supply by 6% and our diesel supply by 1.2%. But the Iowa Farmers are very happy. This is an election year!

Just picked up a copy of Automotive Engineering Journal and there’s an article on Renault of France tweaking their compact Logan diesel (not a hybrid!) to 2.72 km/liter or 86.7 mpg on a 110 mile test route. This is a car the size of a Hyundai Accent, and very driveable.

This should be the direction to go; alternative fuels are expensive, and can only supply a small fraction of our needs. Growing more sugar cane can produce more alcohol, but there are limits. The best way to back out imported oil is to use much less of it!

Rocketman; sorry misprint, that mileage was 2.72 liters/100km.

Thanks, Docnick

It doesn’t,Ed. So, thanks

“Was this additive a requirement by the gov’t to reduce emissions?”

No, it was required to reduce the likelihood that ground water would be contaminated with a dangerous substance. MTBE was used to increase the octane rating of gasoline, but underground gasoline storage tank leaks led to ground water contamination with MTBE. The gasoline would degrade soon enough, but the MTBE would not. Ethanol is not dangerous in the profoundly small quantities that might cone from a gas storage tank leak, and it would degrade quickly anyway. MTBE is still allowed in some areas.

MTBE has been around for some time as a gasoline additive, but in smaller amounts. The EPA oxygen requirements about a decade or more ago resulted in a huge increase in MTBE, or ethanol, both of which add oxygen to gas. At one time the extra oxygen resulted in better combustion, but new technology makes the requirement somewhat moot. In the meantime the oil companies began to depend on the additives, which add up to 10% volumn and would have a problem meeting requirements without either. MTBE caused groundwater problems so everybody is switching to ethanol, but some amount of MTBE is probably still in the gas.

Thanks guys! I knew that someone here would know the answer. Rocketman