Essentially, spark plugs are the pulse of your engine. It forces electricity to arc across a gap and the electricity must be at a very high voltage. As the piston travels up the first time, compressing the air-fuel mixture inside the combustion chamber, the distributor sends an energy surge along the spark plug wire. Once the piston reaches the top, the spark plug fires, igniting the air-fuel mixture and forcing the piston back down, creating power. As you can see, the spark plug is a very important part of the engine. Therefore, in order to maintain the highest performance a car can offer, care should be taken to perform the proper scheduled maintenance in a timely fashion. When your spark plugs are worn out, you will notice a decrease it power and efficiency, so be sure to replace them as soon as possible to restore your vehicle’s performance.