Automobiles of the 21st Century are complex machines comprising thousands of parts. While each has a specific purpose, they all work together to ensure vehicles operate correctly. But what happens when a component deteriorates or breaks down? Is it necessary to replace other surrounding parts?
Unfortunately, the answer isn’t always a simple yes or no. Whether you only have to replace one part or several depends on certain factors, including which one it is and how the other surrounding parts are operating with it. Consider, for example, the relationship between ignition coils and spark plugs. While both are crucial to the ignition system of a gasoline-powered vehicle, each has its own purpose. Because of this, answering the question, “Should I replace ignition coils with spark plugs?” becomes a bit more complicated. Let’s dive deep into the roles of each component and why replacing one or both may be necessary.
How Do Spark Plugs Work?
A car’s spark plugs are the devices that “spark” or ignite the air/fuel mixture inside the engine. By delivering an electric current from the ignition system, spark plugs help create a chain reaction to generate an engine’s power. However, they don’t work alone. To start a vehicle, spark plugs work with several other components, including ignition coils. Specifically, spark plugs change high-voltage electricity from the ignition coils into the spark inside the engine.
RepairPal notes how spark plugs usually break down at around 100,000 miles. However, harsh driving conditions and fluid leaks can cause more rapid deterioration. When the time comes to replace yours, you’ll likely notice the following signs of failing spark plugs:
- An illuminating check engine light
- Difficulty starting the engine and/or vibrations when running
- Rough idling and acceleration
- Engine misfiring
- Decreasing fuel economy
If you or your ASE Certified technician find it time to replace your spark plugs, the average replacement costs can fall between $215 and $288. However, your bill might be higher if replacing your ignition coils is also necessary. But how do you know if that’s the case for you? Keep reading!
What Are Ignition Coils?
Ignition coils are an engine’s electrical parts that work with spark plugs to start the engine. The coils intensify the energy from the battery and alternator by creating the voltage and transferring that power to the spark plugs. Without functioning ignition coals, there is no spark production to start or run a car because of the decrease in power going into the spark plugs.
Several signs can point to a bad ignition coil, including:
- An illuminating check engine light
- A poorly running engine
- A stalling or failing engine
- Lower fuel economy
- Greater emissions
- Sounds of arcing coming from under the hood
Since bad ignition coils equal a poorly running car—and can be a catalyst for more problems—ignoring the issue is not advisable. Instead, getting a tow to the closest repair facility is best to prevent a roadside breakdown and/or further damage. Unlike spark plugs, ignition coils can wear long before reaching 100,000 miles of use. But this isn’t always the case. Some fail before a car hits 10,000 miles, while others break down after reaching the 50,000-mile mark. Therefore, you’ll want to follow your manufacturer’s service recommendations for ignition coils to help prevent failure and maintain your vehicle’s performance. RepairPal reports that the average ignition coil replacement cost is between $215 and $288.
When Do I Have to Replace One or Both Parts?
Now that you better understand how spark plugs and ignition coils work together, you can see why replacing both parts may be necessary. If one breaks down, the other also stops working. But, you only need to replace both components under the following circumstance: Defective spark plugs cause increased strain on your ignition coils, resulting in visible damage. You can skip the coil change when they’re in good shape, and a spark plug replacement is just part of your car’s routine tune-up.
How Can I Stop Mechanical Breakdowns?
Although you can’t stop a car’s natural progression of age and deterioration, following your car’s regular maintenance schedule can help prevent minor problems from becoming more expensive headaches. A skilled mechanic can accurately diagnose any issues you have and answer questions involving strange sounds, smells, or warning lights illuminating your dashboard. This can be especially helpful when overlapping breakdown symptoms—like the ones we mentioned for failing spark plugs vs. ignition coils—make it more challenging to identify the problem. In addition, ensuring you have an extended car warranty with a trustworthy provider can give you the peace of mind you need when facing a sudden mechanical failure. Check our list of top extended car warranty companies for more information on plans and providers.