Your car’s ignition system gets the vehicle going and ensures that it runs smoothly. Spark plugs must fire properly to assure engine performance and emission control. New plugs should be installed at the specified mileage. Check the specification section of your owner’s manual for the proper type of spark plugs for your vehicle. Spark plug wires should also be inspected regularly for evidence of cuts, cracks, splits and corrosion. Also at the time of changing the spark plug wires the distributor cap and ignition rotor should be replaced. Some of the newer vehicles are going to DIS (distributor-less ignition) and COP (coil-over-plug) systems. These systems have ignition coils and/or sensors that send signals to the computer. This is what takes place of the distributor cap and/or spark plug wires. This is a more efficient system because it is computer-controlled, but also can be more costly when replacing them.