A new law goes into effect tomorrow in Oregon requiring gasoline retailers to pump a ten percent ethanol blend. The E10 Fuel standard kicks in on January 15 for these counties in northwest Oregon: Clackamas, Clatsop, Columbia, Marion, Multnomah, Polk, Tillamook, Washington, and Yamhill. A second group of counties will be rolled in by April 15: Benton, Coos, Curry, Douglas, Jackson, Josephine, Lane, Lincoln, and Linn Counties. And the rest of the state must meet the standards by September 16, including Baker, Crook, Deschutes, Gilliam, Grant, Harney, Hood River, Jefferson, Klamath, Lake, Malheur, Morrow, Sherman, Umatilla, Union, Wallowa, Wasco, and Wheeler Counties.

Gas stations in the Portland area already pump a ten percent ethanol blend during the winter months, so some motorists won’t notice a difference. “Gasoline blended with ethanol performs in much the same way that regular gasoline does,” says Earl Baker, AAA Oregon Approved Auto Repair Coordinator. “It can be very difficult if not impossible to detect the difference in engine performance when comparing an ethanol blend to regular gas.”

Baker says there are some changes you should be aware of. “Ethanol is a solvent. It can help clean combustion chambers, and scour your fuel delivery systems, fuel tanks, fuel lines and fuel injectors.” Baker adds that ethanol also attracts water, unlike regular gasoline which repels it, and that could potentially cause problems. He says, “Over time, E10 will break loose any deposits of dirt or water currently suspended in your fuel tank. This could potentially cause fuel filter clogging, and the possibility of fuel injector issues.” Baker adds that ethanol can also cause corrosion and attack certain gaskets and rubber parts in a car engine. But Baker says these issues shouldn’t impact many motorists. “E10 will still have all of the properties of regular unleaded fuel as additives will continue to prevent engine valve recession. People have been filling up with E10 in the Portland area during the winter months and it has not caused major problems.”

You may notice changes in your gas mileage when you fill up your tank with an ethanol blend. Some studies have shown that fuel economy may decrease slightly by one to four miles per gallon, but there are many variables that impact your mileage, including tire pressure, car condition, use of heater or air conditioner, etc.

Auto makers in the U.S. approve the use of fuels containing up to ten percent ethanol, and some recommend it because it burns cleanly. Ethanol can actually make regular gasoline burn more smoothly and slightly cooler because it raises the octane rating of regular gas.

The new fuel standards do help reduce tailpipe emissions of carbon dioxide and carbon monoxide. Fuel containing up to ten-percent ethanol has been certified by the Environmental Protection Agency to reduce carbon monoxide emissions by up to 30 percent.

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