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E 85, destroy my engine?

I have a 1994 lincoln towncar, 55,000 original miles. I accidently put 3 gallons of E 85 in it. Then added 20 gallons of mid grade unleaded. Will my engine be damaged?

You’ve diluted the E85 sufficiently that you should have absolutely no damage.

Your tank now has 23 gallons of which 4.55 are ethanol. With a bit of extra dilution from whatever gas was in the tank when you started.

You now have E19.8, or 19,8% ethanol. By 1994 fuel systems were already being built to withstand ethanol without problems, and I don’t believe the difference between your normal 10% and the 19% you now have will cause an operating problem. If you do feel a loss of power or diminished operation, it’ll go away with your next fillup without having caused any permanent damage. It’ll simply be from the difference in energy in the ethanol and its slightly different detonation characteristics.

Happy motoring.

Well, u did double the value of car when u filled tank.

Thank you. @Cavell, this car runs and rides like a dream. It was a car we bought for my mom, she picked it out. She never drove a car in her life and it sat in the garage for years only coming out when one of us drove her to doctor or to run errands. Now that shes gone, this car is treasured by us. You couldnt place a value on it.

No, but a full tank used repeatedly will definitely do so!

As The Same Mountain bike said, you diluted it enough to avoid any serious issues.

When you get down to 1/2 a tank, fill uyp again and you’ll have diluted it even more.

No harm no foul.


You should not have any long term problems since the E-85 was diluted. A couple of years ago a large regional oil distributorship had an “accident” and released thousands of gallons of gasoline to their stations with a large ethanol content. The result was that no automobiles were ruined but they did suffer engine stumbling and lower fuel mileage. Small engines did suffer and many were destroyed from the higher ethanol content. I lost a weed eater and a push mower to the gas but my trusty old riding mower is still running strong. They never did release the exact figure for the ethanol boost but 25% was the number that most people agreed on. It could have been lower than that or it could have been higher. All I know is…I’ve not bought a single gallon of their gas since this thing happened.

I use real gas in my yard tools. They were not made for ethanol.

“I use real gas in my yard tools”.
@knfenimore–I can’t get non-ethanol fuel in my area. For my 2 stroke roto-tiller, I buy premixed (50:1) non-ethanol fuel for over $5 a liter. My old lawn mower ran o.k. on E-10 but was using a lot of oil. I was able to purchase at a very low price a Black and Decker cordless electric mower–no more fuel worries. It is heavier than my old mower, but I like the quiet operation.

non-ethanol fuel is only legal in NH for marine and aviation use, and maybe for agricultural use (I’m not sure). It’s not legal for on-road use, and not available at most gas stations.

I would burn that fuel off as quickly as possible to get it out of the fuel system…Don’t let is sit for months…

I too would drive out that tank of gas immediately. The engine isn’t the problem. It’s every single o-ring, seal, and other piece of rubber in the entire fuel system. They weren’t designed to deal with that level of alcohol.

I got a call from my wife who was on the road and had stopped at a Coop station for gas. She had accidentally put in a gallon or two of what was labeled for “off road use”. Was worried sick that that was a problem. I said the car will love not having any ethanol in it.

I am so glad that FL now has stations with 89 non-ethanol fuel…My cars require only 87 but going up 2 points is not all that much to 89…you pay a little more for it but great for lawn equipment and my 89 Mustang GT.
In the past 3 years lost 2 weed eaters due to ethanol and had to rebuild the carb on my lawn tractor.FL passed a law last year that we do not need E-10 and real fuel starting to show up everywhere…DROP DEAD EPA ! We even dropped ALL vehicle inspections, safety and emissions. If it runs you drive it…none of this BS not being able to renew your registration if it does not pass smog. If you have car that won’t pass emissions …move here.

My 89 GT now runs 100 % better on straight gas…I am thankful that it did no damage with E-10…Car seems to have better throttle response / more power and better fuel mileage. I also read that the government is trying to push E-15…not good for any car unless its E-85 rated.

Regarding the Town Car that thing is still an infant and with proper care should go a quarter million miles easy.

As to Ethanol, the small engine shops around here always get very busy in the springtime; about the time grass needs to be mowed, weeds trimmed, and tree branches cut. That’s when many people find that the Ethanol that’s been sitting all winter has turned to crap and gummed up the works.

Howie, what actually happened is that the EPA approved E15 as an over-the-road motor fuel in non-flex engines. Hopefully the marketplace will not accept it, hopefully stations that try to sell it will lose their customers to stations selling E10. Or, at least in FL, 89 octane ethanol-free gas… an idea that I hope spreads across the country. It’s time legislators admit that E10 was a bad idea. Of course, as long as they’re feeding off the ethanol producers’ lobby, that’s highly unlikely.

I have a technical issue with ethanol too. Ethanol is allegedly an “oxygenator”, it adds oxygen to the fuel to enable more complete combustion, combustion being only viable when the hydrocarbons are in contact with oxygen. With the capability of today’s injection systems to vaporize fuel, and the capability of today’s metering systems to fine tune the volume of gas being injected and to constantly tweak the mix, I have to wonder of oxygenating the fuel is no longer necessary to achieve full combustion of the hydrocarbon molecules. I have to believe that ethanol is 99.99% politics and .01% better fuel. And at that I’m being generous.

I’ve long believe that ethanol is 1% C2H6O and 99% BS. I’ve yet to be convinced otherwise.

I also heard that regular fuel without ethanol is good for about a year without any stabilizer…Ethanol fuel can go bad between 3 and 6 months. I guess some states just want to keep the farmers in business due to kickbacks.

Don’t these government agencies do tests on engines never designed for E-10 ? When I ran my lawn tractor on E-10 while cranking to start it would always back fire when cranking…since the change to regular fuel, she starts up on the second revolution… We need to get laws passed removing this E-10 from our fuel they are shoving in our engines.

A few months ago Florida shut down one station near me after complaints and they found this station had E-27 going out to consumers…Just because a pump says E-10 or less does not mean anything. Too bad someone has not come up with some tester where we can put a few ounces of gas in a jar and test it on the spot for ethanol content

No harm done but if you buy a car in the future that is designed to use E85 DON’T USE IT.

My shop had loaner cars that were designed for E85 and after a few customers filled the tanks with it the cars started to run like garbage. All because of the E85

When E-10 first hit the market around here, I had a 1978 Oldsmobile Cutlass Salon with a 260 V-8 engine. I didn’t realize that the gas had ethanol from the station where I was filling the tank. We had to crank the car for a longer length of time before it would fire up when the motor was warm. My wife thought about the gasoline and suggested we go to a station that did not have ethanol in the gasoline. That solved our problem. There must have been some changes made when the non-ethanol gasoline was no longer available as the Olds started o.k. on the later ethanol fuel.

It’s a Catch-22. Getting these laws repealed/amended means going against the environmentalists and the agricultural lobbyists. Having that kind of financial power focused on shortening your term in office because you’re attempting to pass laws that adversely affect their industries (yes, environmentalism is an industry) is tantamount to career suicide.

I wish it were more complicated than that. But it isn’t.