March 28, 2024
BANGOR DAILY NEWS (BANGOR, MAINE

High-octane gasoline lowdown

Are you tempted to buy a high-octane gasoline for your car because you want to improve its performance? If so, take note. The recommended gasoline for most cars is regular octane. In fact, in most cases, using a higher-octane gasoline than your owner’s manual recommends offers absolutely no benefit. It won’t make your car perform better, go faster, get better mileage or run cleaner. Your best bet is to listen to your owner’s manual.

The only time you might need to switch to a higher-octane level is if your car engine knowcks when you use the recommended fuel. This happens to a small percentage of cars.

Octane ratings measure a gasoline’s ability to resist engine knock, a rattling or pinging sound that results from premature ignition of the compressed fuel-air mixture in one or more cylinders. Most gas stations offer three lane grades: regular (usually 87 octane), mid-grade (usually 87 octane) and premium (usually 92 or 93 octane). The ratings must be posted on bright yellow stickers on each gasoline pump.

Check your owner’s manual to determine the right octane level for your car. Regular octane is recommended for most cars. However, some cars with high compression engines, like sports cars and certain luxury cars, need mid-grade or premium gasoline to prevent knock.

How can you tell if you’re using the right octane level? Listen to your car’s engine. If it doesn’t knock when you use the recommended octane, you’re using the right grade of gasoline.

Unless your engine is knocking, buying higher-octane gasoline is a waste of money. Premium gas costs 15 to 28 cents per gallon more than regular. That can add up to $100 or more a year in extra costs. Studies indicate that, altogether, drivers may be spending hundreds of millions of dollars each year for higher-octane gas, which they don’t need.

As a rule, high-octane gasoline does not out-perform regular octane in preventing engine deposits from forming, in removing them, or in cleaning your car’s engine. In fact, the Environmental Protection Agency requires that all octane grades of all brands of gasoline contain engine cleaning detergent additives to protect against the buildup of harmful levels of engine deposits during the expected life of your car.

A few car engines may knock or ping even when you use the recommended octane. If this happens, try switching to the next highest octane grade. In many cases, switching to the mid-grade or premium grade gasoline will eliminate the knock. If it continues after one or two fill-ups, you may need a tune up or repair. After that work is done, return to the lower grade gasoline.

Occasional light knocking or pinging won’t harm your engine, according to the Federal Trade Commission, and doesn’t indicate a need for higher octane. But, heavy persistent knocking shouldn’t be ignored because it can lead to engine damage.

The octane rating of gasoline marked “premium” or “regular” is not consistent across the country. One state may require a minimum octane rating of 42 for all premium gasoline, while another may allow 90 octane to be called premium. Know what you’re buying. Check the octane rating on the yellow sticker on the gas pump instead of relying on the name “premium” or “regular.”

If you’re concerned about the accuracy of an octane label, or if you don’t see a yellow octane sticker on a gasoline pump, write Consumers Response Center, Federal Trade Commission, Washington, D.C. 20580.

Consumer Forum is a collaborative effort of the Bangor Daily News and Northeast COMBAT. Send your questions to Consumer Forum, Bangor Daily News, P.O. Box 1329, Bangor 04402-1329. COMBAT is a membership organization with basic dues of $10 a year. For membership information write to the above address. Please enclose a large, stamped, self-addressed envelope.


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