Spark plugs may be small, but they play a big role in how your car runs. From starting your engine to helping it run smoothly and efficiently, these tiny components are essential to vehicle performance. In this guide, we break down what spark plugs do, the signs that they need replacing, and how often you should schedule a change.
Your engine runs by igniting a mix of air and fuel in each cylinder. Spark plugs create the spark that ignites this mixture, setting off a chain reaction that powers your car. Without working spark plugs, your engine can’t start—or run properly.
In short, spark plugs:
If your spark plugs are worn or damaged, they can’t fire efficiently, and your car’s performance will suffer.
Like many vehicle components, spark plugs wear out over time. Here are common signs they might be due for replacement:
Worn spark plugs can cause hard starts or require multiple turns of the key before the engine fires.
If your car shakes or sounds uneven when idling, misfiring spark plugs could be to blame.
Faulty spark plugs can lead to incomplete combustion, making your engine work harder and burn more fuel.
If you notice sluggishness or hesitation when accelerating, old spark plugs may not be providing a strong enough spark.
A misfiring engine can feel like your car is jerking or surging, often accompanied by a check engine light.
Pro Tip: Modern vehicles often include onboard diagnostics that can detect misfires. If your check engine light is on, it could be time to inspect your spark plugs.
Get Your Spark Plugs Checked by the Pros and keep your engine firing on all cylinders
Book a spark plug inspection or replacement at your nearest Repco Authorised Service Centre today.