According to a new study from AAA, researchers extrapolated from a consumer survey to determine that 16.5 million motorists filled up unnecessarily with premium gas an estimated 270 million times in the last year.
Having determined how many motorists were buying premium gas in place of regular, AAA continued with laboratory research to see if that premium gas conferred any benefits. Using a dynamometer -- essentially a treadmill for cars -- researchers determined that using premium in cars that require only regular did not increase power or gas mileage, nor did it cut down on polluting emissions.
The AAA research came up with some additional findings:
• 70 percent of Americans drive cars that need only regular gas, while 16 percent require premium and the remaining 14 percent need mid-grade gas or have an alternative power source like electric batteries.
• Modern engine-control systems can adjust automatically to deal with any problems from lower-octane gas, a capability not available in earlier decades.
• Getting scheduled maintenance done in a timely manner will help keep gas mileage higher and help the engine run better.
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