Many people do not believe Atle Erlingsson, spokesman for the California State Automobile Association, when he tells them that they don't need to buy premium gasoline for their cars. More than 90% of cars run perfectly fine on regular. It is purely a myth that premium gas is cleaner, improves mileage and overall is better for your car. One case where you may need a higher-octane fuel is if you hear a knocking sound after filling up.
But Mr. Erlingsson says let your mechanic or auto manufacturer tell you whether you need to buy premium, not an oil company. By switching to a lower-priced fuel, the average driver will save about $200 a year. Some of that savings can be put toward oil changes every 3,000 miles. That will make a bigger difference in your car's performance than premium gas will.