Parts for your 2020 Subaru Impreza-Ignition leads

Understanding Ignition Leads and Their Role in the 2020 Subaru Impreza

When it comes to the 2020 Subaru Impreza, ignition leads are actually not part of the engine's ignition system. This is because modern vehicles like the Impreza utilise more advanced ignition technology that has made traditional ignition leads redundant. In older engines, ignition leads, also called spark plug wires, were essential components. They carried the high-voltage electricity from the ignition coil to the spark plugs, which in turn ignited the fuel-air mixture inside the engine cylinders. However, Subaru's 2020 Impreza takes a more modern approach with a distributor-less ignition system that uses ignition coils placed directly on top of each spark plug, known as coil-on-plug ignition.

This change means there are no longer any ignition leads needed to route electricity across the engine bay. By having the coil-on-plug setup, electrical losses and interference are minimised, and ignition reliability is improved. It also reduces the number of parts that require regular maintenance or replacement, simplifying servicing for owners. So, if you are poking around looking for ignition leads on your 2020 Subaru Impreza, you won't find any - because they just aren't there.

For those curious about older vehicles or just wanting to understand what ignition leads do and why this shift has happened in cars like the Impreza, here's a deeper dive into ignition leads and their maintenance.

Ignition leads were traditionally a key part of the ignition system in many petrol engines. Their main job was to transfer the high-voltage electrical charge generated by the ignition coil to the spark plugs. The spark plugs need this charge to create a small but powerful spark that ignites the fuel-air mixture inside the combustion chamber. If the ignition leads fail or degrade, the spark strength diminishes, leading to rough engine running, misfires, poor fuel economy and higher emissions.

Ignition leads are typically made of an insulated copper or carbon core wire with a rubber or silicone protective outer layer. Over time, heat from the engine bay, exposure to oil or fuel leaks and simple wear and tear can cause the insulation to crack or degrade. This can result in electrical leakage or cross-firing between adjacent leads, affecting engine performance. Therefore, regular inspection and replacement of ignition leads were important parts of routine servicing for many vehicles before the coil-on-plug era.

For vehicles equipped with ignition leads, a few helpful tips can keep them running well:

• Regularly inspect the leads for visible signs of wear like cracks, brittleness or burn marks.
• Check for a secure fit at both the ignition coil and spark plug end to prevent voltage loss.
• Replace ignition leads in sets during servicing, even if only one lead looks faulty, to maintain consistent performance across all cylinders.
• Use ignition leads with quality connectors and insulation to ensure durability and optimal electrical conduction.

Replacing ignition leads involves disconnecting the old leads one at a time to avoid mixing up the firing order. New leads should be routed carefully to avoid contact with hot engine parts or sharp edges. It sounds technical but for professional workshops or knowledgeable DIYers, it is a straightforward job.

While ignition leads require some attention in older cars, Subaru's move to coil-on-plug ignition means 2020 Impreza owners don't have to worry about this part. Instead, their maintenance focus shifts to checking and replacing ignition coils and spark plugs directly. The coil-on-plug design allows for a more compact and reliable ignition system that offers better engine performance and reduced maintenance needs.

So, for anyone maintaining or servicing a 2020 Subaru Impreza, ignoring ignition leads is perfectly fine because the car does not have any. Instead, owners should focus on ensuring that the ignition coils and spark plugs are serviced at recommended intervals to keep the car running smoothly and efficiently.