Spark plugs provide the spark needed to burn gas in your engine. The "spark" made by your spark plug is like a tiny bolt of lightning; it's that powerful. Each time it sparks, a wee bit of material is lost from the electrodes. Over the millions and millions of sparks that happen over the thousands of miles you drive, enough material is lost from the spark plug to affect its performance. That's one reason they need to be replaced.
It’s also critically important to have the right type of spark plug for your vehicle. Engines are design to run with different internal temperatures. Spark plugs are design to run with specific temperatures as well. Your special advisor will be able to determine the right plug for your vehicle and when to replace your spark plugs as well.