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Going top tier and also considering ethanol free gasoline

I read the owners’ manual on my 2012 Chevrolet Manual and became aware of top tier gasoline. I am going to use it because I have several gas stations locally and it is the same price so that is not a question I want information on or debated.

The question is, Countrymark is a Top Tier Vendor and offers ethanol free fuel in 91 octane. I am wondering if my 4-cylinder Honda Accord or Chevrolet Malibu will gain enough mpg to offset the additional price of 91 versus 87 octane.

No…your car is designed to run on what’s out there. Will your car not suffer from some ill effects of ethanol ? Yes, if you let the vehicle sit for extended periods and not make provisions to prevent gas/ethanol problems. But if your car is a daily driver, it’s only a fuel system issue as gasoline is made to standards and cars are designed to work with it…as long as it’s fresh.

It’s worth it to buy ethanol free gas for machines that sit with the gas in it for extended periods, like your mowers, out boards and snowmobiles. Otherwise, buy what’s the appropriate actane rating and the cheapest.

Top Tier is a description of the quality of detergent additives put in gasoline. A dirty secret in the gas industry is that ALL gasoline, no matter the refinery, is the same and usually mixed. Gasoline is distributed throughout the country through pipeline systems. When Exxon puts 100 gallons of 87 octane gasoline into the pipeline, they get immediate credit to pull 100 gallons of 87 octane from the pipeline. However, chances are the 100 gallons they pull will NOT be the same from any of their refineries, but is most likely from another source, like Conoco Phillips or Citgo. The only difference is the additives that get added at the pipeline depot before the trucks deliver it to the gas station.

As far as using 91 octane, you’ll never see a bump in fuel mileage. The engine in you Malibu and Accord are designed to run on 87 octane. Adding 91 octane will not make any difference except to your wallet. Klick-and-Klack has a great article discussing this issue.

If your looking for Top Tier fuels, look here.

And, chances are, you will not see any mileage improvement with ethanol-free fuel. The 2012 models were designed with ethanol fuels in mind, probably even to the 15% ethanol level proposed by the EPA. And there are some models that even allow for E85 (85% ethanol) with the flex-fuel engine. These cars are already tuned to get the best mileage based on available fuels and the difference in E0 to E10 is not enough to detect. It is definitely not enough to make up a $0.30 to $0.50 per gallon difference.

The octane won’t make a difference. But the lack of ethanol might. So just try it - do about 1,000 miles on the ethanol free and calculate mpgs. Then do another 1,000 with an 87 with ethanol.

I doubt you’d ever come out ahead, but the mileage should actually be slightly better without the ethanol. If nothing else I’m just curious.

I disagree with the folks above. Ethanol-free gas has a higher energy content than E10 gas, so it should give you better fuel economy. It’s worth trying a few tanks of each to see which one is actually cheaper. (The octane is irrelevant here.)

E10 has been mandated in NJ for years. I don’t believe ethanol-free gas is available in this state. Other than a 5-10% drop in mpg, my GM vehicles (93 Caprice, 2000 Blazer, and 2010 Cobalt) have had no log-term issues with E10. I doubt you’ll will see any improvement switching from 87 to 91 octane.

Ed B.

Worth a try, there’s 3% more energy in ‘pure’ gas, and there might be some slight improvement with 91 octane from the engine running slightly more advance. How much more does it cost than the regular you would use?

I think you will get more mpg from ethanol free gas. The question is whether it is worth the price? The 91 octane gas could be $.30-.40 more per gallon. Let’s guess the price is 10% higher. This means you need to get 11% or more mpg just exceed breaking even. If you drive further to get the 91 octane that needs to be factored into the equation. Assuming you get 30 mpg from 87 in the Malibu. You would have to get 33.3 mpg from the 91 octane to breakeven. So, all you can do is try a few tankfuls of each and keep very good records, then you can answer your own question.

You might have to repeat the experiment with each car. If one has a knock sensor it might benefit more from the 91 than a motor without a knock sensor. A knock sensor allows the computer to advance the timing which gets more efficient use of the 91 octane gas.

Your owner’s manual recommends Top Tier gasoline not because it will provide you with better mpg (it won’t) but because it is supposed to reduce deposits in your car’s combustion chamber. Gasoline must pass some rigid tests to earn the Top Tier rating. If the manual recommends it, I suggest you always use it.

The use of E10 vs. ethanol-free fuel is still being debated. If ethanol-free fuel is available to you, and at the recommended octane, then prefer it. If you have to go up in octane, higher than the recommended fuel for your car, you would be losing money.

I just spoke with my neighbor. He and his wife had identical 2001 Saturns except for the transmissions. He said he rarely drove his wife’s car, but when he did he noticed that it ran better than his. Unknown to him she was using 91 octane and he had been using 87. Upon switching his vehicle to 91 octane he said that over a period of 3 months he noticed a gradual improvement in his car; at the end of 3 months was running as well as his wife’s. I am going to try the 91 octane ethanol free and see what happens.

If you look hard enough, you can sometimes find a gas station that sells ethanol free regular gas - they’re catering to the people filling small-engine things like lawn mowers, which until recently didn’t do well on ethanol.

Ethanol-free gas is chiefly available in rural farming areas. If you don’t live in that type of area, you are likely to have a hard time finding ethanol-free gas.

In Indiana ethanol free gasoline seems to be vailable only in rural farm cooperatives, small marinas and airports, and occasional rural gas station; only 25 locations listed in the whole state. Then it is almost exclusively 91 octane. Reason given somewhere is that gasoline sold must average 7.5% ethanol content so the least purchased octane only is offered ethanol free which seems to be a reasonable explanation.

There is no reason to avoid ethanol gasoline mix. Unless you want to give a Saudi a bigger share of your money. The ethanol is made here in the US and about 40% of the gasoline is US. Then a bunch of overseas vendors like venezuela who hates us but we own the refineries that crack thier crude. Ethanol has a 15% less punch as a fuel but it is home grown and it causes a lot less air pollution. Your take away is that a normal car will see less than a 2% fuel economy change. Our air pollution from gasoline not burning completely goes down about 40%. Gasoline was never a perfect fuel. Now we are trying to blend a fuel that does not cause people to die as often due to air pollution.

Anyone who thinks ethanol brings any significant reduction in air pollution is being sold something. The “something” they are being sold is marketing stuff from the corn and associated agricultural industries where one ignores all of the energy/pollution that actually went into planting, growing, harvesting, and processing the corn into burnable fuel. Does it burn cleaner than gasoline in an engine? Yes. But how much carbon was dumped getting it into the tank? Corn-based ethanol is a bust. Environmentally speaking it might be no worse - but that’s about it.

I have no option but to buy gas with ethanol unless I take a road trip, due to epa mandates. Octane of 91 need should be determined necessary by the owners manual. I possibly stupidly waste my money on mid grade bp shell or mobil, but see many cars at any stations filling up on the cheapest gas still run fine.

Dekindy wrote:
I just spoke with my neighbor. He and his wife had identical 2001 Saturns except
for the transmissions. He said he rarely drove his wife’s car, but when he did he noticed
that it ran better than his. Unknown to him she was using 91 octane and he had been
using 87. Upon switching his vehicle to 91 octane he said that over a period of 3 months
he noticed a gradual improvement in his car; at the end of 3 months was running as well
as his wife’s. I am going to try the 91 octane ethanol free and see what happens.

This doesn’t sound like a very controlled experiment. Higher octane does nothing to make your car run better gradually over a period of time. If your car does not need the higher octane, then it does nothing to help your car run better.

Something else is likely a factor with your neighbor’s experiment.

Why make a $3 donation to the oil companies every time you fill up?