Your fuel injector cleaner manufacturer will indicate as to how and why you need to clean your injectors. There is usually clear instructions on how and when to use the injector based on the miles driven or after specific period of time.If you have recently bought a new car, it would be pointless and useless to use a fuel injector cleaner. However, there are some cleaners that are made to be used in new vehicles as they prevent the injectors from getting dirty in the first place.If you have your car for a while now and you also notice some strange things when the engine starts, such as loss of acceleration, louder than normal engine sounds, darker fumes etc. then it is a clear indication that you need to feed your car with a fuel injector cleaner formula.Moreover, if you plan on storing your car for a few months, we highly recommend draining the existing fuel with a fresh formula so that when you start it again after a couple of months there is no residue left in your car’s engine.