What is RFI?

Radio Frequency Interference (RFI) or electrical "noise" is caused by ignition systems, alternators, wiper motors, etc., but the ignition system causes the strongest "noises" and they include a wide range of frequencies. This noise can cause interference with the operation of radios, electronic components, fuel injection systems, depth finders, and other sensitive electronic equipment. Resistor plugs, wires and spark plug caps are used as a RFI suppression system to reduce this noise.