The fuel filter is an in line filter that catches impurities that are in your gasoline. When they have a few miles on them (5-8,000 miles) ,they can become clogged and cause bad fuel milage and decreased engine performance. They should cost less than $10 and shouldn't cost more than $35-45 to have installed. This will help get you some more miles per gallon and probably make your car run a little smoother if its been on your car fora while.
