Individual coil Packs

Overview

Way back in the early 1900s, ignition coils were becoming more familiar to people because they were a key piece of every automobile engine. The ignition coil would take the low voltage from the battery and amplify it with the magic of magnetic fields. That higher voltage output was then sent out to the spark plugs where it ignited the air fuel mixture inside the engine. Over one hundred years later, ignition coils look different, but still work the same exact way.

Ignition Coil - Distributor-Style

This type of simple, two wire ignition coil was used from the late 1920s until the 1980s. Inside it lives a set of "primary" and "secondary" coil windings that are both wrapped around a piece of iron. When the primary winding is fed power, a magnetic field builds up inside of the coil. If power is then momentarily cut off, the magnetic field inside collapses and it produces a high voltage spike out the secondary winding that is used to fire the spark plugs. With this system, one ignition coil is producing every single spark for every spark plug. That can be quite a workout for the ignition coil at high RPM's!

Electronic Ignition

By the 1980s, car and truck manufacturers were consistently using electronic ignition. "Electronic ignition" basically meant that a computer told the ignition coil(s) when to fire, based on sensor inputs. This allowed for better engine control, and more importantly, fewer emissions. Around the same time, that electronic ignition was splashing into the automotive scene, the world began to see ignition coil packs, coil-on-plug ignition, and the waste spark ignition system.

Ignition Coil Packs

Coil packs are a group of ignition coils that are physically connected together, but provide one ignition coil per cylinder. They are controlled by a computer, which means that distributors, points, and condensers are not needed. The beauty of coil packs is that they provide an extremely large spark to each cylinder whenever the computer asks for it. Their downfall is that if one of the coils within the pack fails, the entire ignition coil pack needs to be replaced. Whole ignition coil packs can potentially be pricey depending on the technology inside them, and the vehicle application.

Coil On Plug Ignition

These days, most car and truck manufacturers have begun to use "Coil On Plug" ignition or "COP" for short. COP ignition has one individual ignition coil sitting on top of each individual spark plug. This means that spark plug wires are no longer needed at all, and each cylinder gets a superbly timed and powerful spark. The great thing about this type of ignition system is that if one ignition coil fails, that is the only one that needs to be replaced (Read: cheap to fix!). The other huge benefit is that, if you are trying to diagnose a misfire issue, you can swap two coils around to see if the misfire moves to the other cylinder. Ignition problem diagnosis becomes a piece of cake!