There is a specific Saturn spark plug made for each type of engine from this GM car maker. The recommended spark plug has to be used not only so the expected performance of the Saturn can be achieved but so the longevity of the engine can be maintained. There are many vehicle owners that are unaware of what kind of severe damage placing the wrong type of Saturn spark plug in their engine can actually do. If a replacement spark plug is randomly placed in your engine and its heat range is too high for it, the top of the piston will be damaged. If this hot spark plug is left for too long of a period in the Saturn engine as it is operating, then a hole will eventually be created in the top of the piston rendering the engine inoperable. Another variable in the different types of spark plugs used in Saturn engines is the depth at which they go into the engine. If the plug is too short, it will be incapable of igniting the air and fuel mixture in the combustion chamber causing the engine to run rough and not be able to perform as expected. If the plug is too long and reaches too far into the combustion chamber, it could come in direct contact with the top of the piston damaging both parts. For these and many other reasons the right spark plug should always be placed in your engine when it is undergoing a tune up procedure. It is the only way to ensure the maximum performance of your vehicle can be achieved. It is also the only way to be positive the plug will not damage your engine when you are operating your vehicle.