For an internal combustion engine to operate, many different individual components have to work in perfect harmony. Fundamentally, a potent mix of fuel and air has to be ignited at just the right moment, to force the pistons to turn the engine. This act of ignition is controlled by a powerful component known as a coil and should it start to fail, many problems can materialise. What do you need to know about the ignition coil, and how can you tell if it is in need of replacement?
As you know, the source of power in a typical car or truck is the humble, 12 V battery. When you turn the key in the ignition, this battery is connected to various components, with the means to start the vehicle. However, this amount of power is by no means enough to activate the ignition process. After all, this will rely on the generation of a high-voltage spark that jumps between two terminals, in order to cause a controlled explosion.
This is where the ignition coil comes into its own. It is able to convert the battery power into something that is many times more potent and will do so on a continuous basis while the vehicle is in motion.
Some modern-day cars have more than one coil, with an individual unit attached to each engine cylinder. These have to be carefully controlled through sensors and other software, all linked with the central ECU.
If the coil begins to fail, you will undoubtedly notice issues with performance. In the beginning, these problems may be more subtle, with a slight loss of acceleration or a larger bill at the fuel station. As the issue gets progressively worse, however, you may notice a misfire and the engine will sound a lot rougher during everyday operation. Nevertheless, it may take much longer for a big issue to arise, should the vehicle have a series of individual coils instead of one central unit.
It's important to take action as soon as you notice that something is amiss. Otherwise, the coil (or coils) may fail completely, and you would be stranded at the side of the road. Remember, that when you do replace these units, make sure that you only buy the highest quality. After all, a typical ignition coil has to deal with a great deal of abuse, high temperatures and constant operation.
Consider finding a dealer who works with your specific car and parts like Bosch authorised dealers.