Timing and order is very important in many things. But do you know that these two things are also very important in the proper operation of your GMC's engine? For the engine to function properly, the movement of its individual parts (the pistons, the valves, the fuel injectors, and the spark plugs, in particular) must be timed correctly. All of these components must also run in the proper order so as to ensure the engine's smooth operation. This order and timing is controlled by a variety of components. As for the order and timing of ignition in the spark plugs, the GMC distributor would be held responsible.
The GMC distributor is that part of ignition system on older and some late model GMC vehicles which routes high voltage pulses from the battery to the spark plugs in the proper firing order. Most new GMC vehicles would no longer make use of distributors. Instead, these late model trucks would feature a distributor-less ignition system that uses direct ignition for igniting the spark plugs.
In GMC vehicles that still makes use of distributor-based ignition systems, the GMC distributor may rightly be called the heart of the system. Typical ignition distributors are made up of two primary parts: the rotor, which is connected by the ignition coil to the terminals of the battery, and the distributor, which holds the contacts for the individual spark plugs. From the battery, high voltage pulses would be carried into the rotor. The rotor in turn passes this high voltage pulses to the contacts as it passes close to each. From the contacts, these pulses would flow through the spark plug wires until they ignite the spark plugs in the cylinders.
The timing and order of spark plug ignition is very important for the proper operation of the engine. Central to this very important function in older GMC vehicles is the distributor. As a mechanical component, however, GMC distributors have the tendency to malfunction as it grows old. This is one of the major reasons why new GMC vehicles no longer feature distributors.