What is the function of a spark plug?
A. The spark plug is the last step in the ignition circuit. It takes a voltage surge from the coil to the distributor cap then to the rotor back through the distributor cap to the plug wires, and provides a path for the high voltage spark that ignites the compressed air fuel mixture within each cylinder. If everything is working properly and the correct amount of fuel is used, even burning of the compressed mixture results. The piston is pushed down, the crankshaft turns, and the engine runs efficiently. This provides maximum fuel economy and lowest exhaust emissions.
