Even though they fit in the palm of your hand, spark plugs are an essential part of your engine. They’re responsible for creating an arc of electricity that ignites the air-fuel mixture inside the engine, putting the pistons in motion and allowing you to get from point A to point B. It seems straightforward, but this post from our car maintenance team will explain everything you need to know about spark plugs, especially for drivers using E85 fuel.

Understanding heat range

In addition to igniting your air-fuel mixture, spark plugs are responsible for transferring heat from the combustion chamber to the cooling system. The plug’s ability to dissipate heat is known as its heat range. You’ll often hear a spark plug described as “hot” or “cold,” which refers to its heat range. Using the wrong spark plug for your engine and fuel could result in premature spark plug failure.

What causes spark plug failure?

Spark plugs wear out over time due to overheating, oil contamination and deposit buildup. That said, you can expect your spark plugs to last for at least 20,000 miles before they need to be replaced.

A few signs that your spark plugs are going bad include “knocking” under the hood, poor performance and increased fuel consumption. If you notice any of those signs or if you’re reaching the 20,000-mile mark, bring your vehicle to a car maintenance pro to have the spark plugs replaced.

Checking the spark plug gap

All spark plugs must have a gap between the center and ground electrodes, and the gap must be the correct size for your engine. A gap that’s either too large or too small can cause a loss of power, engine misfires and poor gas mileage. Read your owner’s manual to verify the recommended gap and ensure you’re following the guide when installing your spark plugs.

If you notice any engine issues and think they may be related to your new spark plugs, use a gap gauge tool. By running the tool through the electrodes, you can determine the gap and make any necessary adjustments.

Why do I need different spark plugs when running E85 fuel?

A growing number of drivers are choosing E85 fuel these days, which provides better engine performance and is more eco-friendly. E85 fuel is composed of 85 percent alcohol, which burns cooler than gasoline. For that reason, you need spark plugs with a lower heat range designed to run with a cooler engine. We recommend only buying OEM spark plugs (with the exception of copper plugs) if you’re running on E85 fuel.

With stock spark plugs designed for E85 fuel, you can trust that you’ll get better performance while reducing fuel consumption and getting a longer lifespan out of your spark plugs.

Let us change your spark plugs

If you need to replace your spark plugs—or need any high-performance car maintenance—come to Fine Line Imports. We only install the best OEM spark plugs specifically designed to ensure your engine performs to the best of its ability. We’re currently open by appointment only, so give us a call today to schedule your in-person visit.