Your engine has three basic needs. Air, fuel and spark. Spark can be the downfall of engine performance, and emissions. This includes spark plugs, ignition boots, ignition coils and ignition wires. If you have an older vehicle, this system may have an ignition rotor and cap. All of these components have to be in tip-top shape to provide a strong, well timed spark to keep your daily drive smooth and healthy. Spark plugs may need further diagnoses of other systems if they are fouled with oil, or carbon. All repairs are priced as such; Price of part, plus installation fee, plus old part recycling, plus trip charge.