Will spark plugs improve gas mileage?
Will spark plugs improve gas mileage? The National Institute for Automotive Service Excellence indicates that bad spark plugs can decrease fuel economy by up to 30%, and can cost drivers up to about 94 cents per gallon at today's prices. 1 If a car's gas mileage suddenly drops, there's a good chance it's because of misfiring spark plugs. What is the purpose of a tune up? The tune-up activity is the act of ensuring the burners are properly mixing the air and fuel and of reestablishing the most appropriate amount of excess air throughout the operating range of the boiler....