Ignition System

The ignition system is responsible for producing the sparks necessary to ignite the air-fuel mixture inside of each engine cylinder. Older vehicles will utilize a mechanical distributor with a set of wires to transmit the sparks to each spark plugs, while modern vehicles are electronically controlled and have the coil pack situated above each spark plug.

Key parts of a vehicle ignition system

Ignition Coil

The ignition coil draws electrical power from the battery, increases its voltage, and sends the high-voltage power to each of the spark plugs. Two winding coils inside of the ignition coil converts the electricity from low to high voltage before sending it out.


In older vehicles, a mechanical component known as the distributor collects high-voltage electricity from the ignition coil and distributes it to each of the spark plugs through ignition wires. Modern vehicles do not have a distributor and instead have the ignition coil pack sit directly on top of each spark plug.

Spark Plugs

Spark plugs use high-voltage electricity to create the spark that ignites the air-fuel mixture and begins the internal combustion process. There is at least one spark plug for each engine cylinder and some vehicles may have multiple spark plugs per cylinder.

Ignition Control Module

In older vehicles, the ignition control module is a separate computer system that controls the firing of the spark plugs. In modern vehicles, this process is controlled by the engine control module, a different computer, instead.

Crankshaft Position Sensor

The crankshaft position sensor measures the rotational speed of the crankshaft and sends this data to the engine computer. If something goes wrong with the crankshaft, the position sensor will detect it and trigger a trouble code or dashboard warning light to alert the driver.

Ignition system maintenance

“Tune-ups” are a part of your routine vehicle maintenance that help keep your ignition system running smoothly without issue. Refer to your manufacturer’s recommended intervals for how often to get a tune-up so that you can avoid most ignition system problems. The spark plugs will eventually go bad and need to be replaced as well. Occasionally, something might go wrong with the ignition system, requiring you get it repaired by a car care professional outside of these routine maintenance visits.

The best way to get maintenance done on your ignition system is to book your appointment through CarAdvise. CarAdvise makes car care simple and guarantees that you’ll pay less than retail price on all car maintenance services.