They work SO good to restore performance and gas mileage. Anyone that hasnt used fuel injector cleaner in a while or never should seriously use some with the next fillup. I have been using it every time I get gas for a week now and my car is running so good that I have to check under the hood and make sure that there isnt something wrong with the intake because its quicker than normal and sounds better. And the awsome thing about it is, its only 2-3 dollars for a bottle. Pick some up next time your at the gas station, you will be pleased.