How Often Should Spark Plugs Be Changed?

A vehicle’s engine needs a spark to ignite the mixture of fuel and air to start and keep the engine running. Without the spark, the engine can’t work and you won’t be able to drive your automobile. This spark is created by a small lightning bolt called a spark plug. Discover how often should spark plugs be changed and the best way to change them on your vehicle.

 

These little devices need regular maintenance just like any other part of your vehicle and they also deteriorate over time and you need to replace them to enjoy a smooth driving experience. Let’s discuss how often spark plugs should be changed.

 

When Should Spark Plugs Be Changed?

There are different types of spark plugs available in the market and each type deteriorates at a different rate. So, the lifespan of a spark plug depends upon its type. The best way to find out the spark plug change interval is to follow the recommendations of your vehicle’s manufacturer.

 

Generally, there are two different categories of spark plugs, which are conventional and long-life. The conventional plugs are made of copper or silver and they’re mostly used in older models. The long-life spark plugs are made of iridium or platinum and they’re used in modern and high-performance vehicles.

 

If you’re using conventional spark plugs, you should change them every 30,000 to 50,000 miles. On the other hand, the long-life spark plugs should be changed after every 60,000 to 150,000 miles. Other than the type of spark plugs, there are some other common factors that can affect the lifespan of your vehicle’s spark plugs.

 

Engine Condition

 

The overall condition of your vehicle’s engine affects the rate at which spark plugs deteriorate. Keeping your vehicle’s engine in a good condition not only allows you to enjoy better overall performance but also increases your spark plugs lifespan.

 

Driving Habits

 

Your driving habits also affect the longevity of your engine’s spark plugs. If you usually drive at high speed, you’ll need to replace your spark plugs more frequently.

 

In order to make sure that you change your engine’s spark plugs at the right time, get them checked after 30,000 miles.

 

Symptoms that Indicate that You Should Change Your Spark Plugs

 

Multiple signs indicate that your spark plugs are worn out and need to be changed and the most common ones are listed below:

 

Check Engine Light

 

If you see that the check engine light on your vehicle’s dashboard has turned on, it’s time to change your spark plugs. Almost all modern vehicles come with a check engine light that can indicate many problems regarding your vehicle.

 

Trouble Starting

 

If you feel that your vehicle is facing a hard time starting or stalls, the worn-out spark plugs can be the culprit. The same problem can occur due to a faulty battery, and you’ll need to check both to find out the root cause.

 

Poor Fuel Efficiency

 

Spark plugs that have reached the end of their lifecycle can lead to more fuel consumption as they fail to burn the fuel effectively. According to the NIASE (National Institute for Automotive Service Excellence), a worn-out spark plug can reduce the fuel efficiency of your vehicle by up to 30 percent.

 

Rough Engine Idle Experience

 

If you notice that your vehicle’s engine is making knocking, pinging, or rattling noises, you need to get your spark plugs checked. If your engine’s spark plugs are worn out, you’ll hear these noises while your engine is in an idle state.

 

Very Slow Acceleration

 

If your vehicle has decreased its acceleration speed and it’s not responding as it normally does, it might be time to change your spark plugs.

 

Manufacturer’s Recommendations

 

It’s best to follow the recommendations of your vehicle’s manufacturer if you want to keep your vehicle in a good condition. In addition, if you have used your spark plugs for the number of miles that your manufacturer recommends, you must change them before they start damaging your vehicle’s engine.

 

If you continue driving your vehicle with worn-out spark plugs, you might need to pay a whole lot of money to get your engine repaired.

 

Can You Change Your Engine Spark Plugs?

If you’re not mechanically sound, you should take your vehicle to a certified mechanic to get your spark plugs changed. However, if you’re a DIY enthusiast and mechanically inclined, you can change your engine’s spark plugs on your own by using the following process

 

Step 1: Remove the Spark Plugs

 

The first step is to remove the spark plugs from your engine and it can be done in the following manner.

 

1. Disconnect your engine’s battery terminals.
2. Blow out the area around the engine’s spark plugs with a vacuum to make sure that no dirt particles enter the spark plug socket.
3. Remove spark plug covers/boots. Make sure that you retain the order by using masking tape for labeling to remember which spark plug belongs to which wire.
4. Remove spark plugs and check them for foreign materials, carbon buildup, or damage.

 

Step 2: Inspect the Spark Plugs

 

Step 2 is to perform a thorough inspection to discard only the worn-out spark plugs and it can be done in the following manner.

 

1. As part of normal wear, all the spark plugs will have slightly brown or black coloring. You’ll also need to look for gasoline, oil, or carbon buildup.
2. Check the center electrode of each spark plug and if it’s correctly shaped and relatively even, you won’t need to change it. However, if you have used your spark plugs for the recommended number of miles, you’ll need to change them regardless of their condition.
3. Use the gap measuring tool to calculate the spark plug gap and close the gap with a gap tool gently if needed.
4. Use a non-metallic brush to lightly rub the spark plug to get rid of dirk or carbon buildup. After that, spray the spark plugs with a carburetor or brake cleaner and wipe dry gently.
5. Discard the spark plugs that need to be replaced.

 

Step 3: Add New Spark Plugs

 

1. If you’re using brand-new spark plugs, then typically, you won’t need to adjust their gap. However, it’s advisable to double-check and use a gap tool for adjustment if needed.
2. Spark plug sockets usually have rubber boots or magnets to keep them in place. Gently insert the spark plugs into their sockets and make sure that you don’t over-torque or cross-thread the new spark plugs.
3. Use a torque wrench to secure the spark plugs in place according to your vehicle’s torque specification.
4. Place the plug boots using the labels to their specified plugs.
5. Reconnect your engine’s battery.

 

What to Keep in Mind While Changing Spark Plugs?

 

First of all, you need to choose the right spark plugs for your vehicle according to the manufacturer’s recommendations. Make sure that you don’t simply buy the cheapest option as it can damage your vehicle’s engine.

 

You might also need to use different types of tools and supplies to make the spark plug changing process easy. Some common supplies include a gapping tool, universal joint extension, ratchet extension, spark plug socket, ratchet, vacuum, non-metallic brush, carburetor or brake cleaner, and a torque wrench.

 

Place all these tools nearby so that you can easily use them while changing the spark plugs. It’s critically important not to let debris and dirt make their way to the spark plug socket. Otherwise, these small particles will reach your vehicle’s engine and can lead to serious damage.

 

Another important thing to keep in mind is that your vehicle’s engine must be cool before starting the spark plug replacement process. That’s because a hot or warm engine can cause damage to the threads.

 

While changing the spark plugs is a doable process, it can be very challenging and you can damage your engine if you’re not mechanically sound. Therefore, if you’re not 100 percent sure of every step of the process, you should take your vehicle to a certified mechanic to avoid making an expensive mistake.

 

How Much Does Spark Plug Replacement Cost?

 

The cost of replacing your spark plugs varies depending upon multiple factors. The platinum and iridium spark plugs are more expensive than copper or silver ones.

 

Generally, the entire process will cost you somewhere between 50 to 300 US dollars. Keep in mind that you might need to pay a little more amount of money depending upon your car as well as area.

 

The best way to find out the amount of money you’ll need to spend is to visit your local automotive parts store or mechanic. Lastly, you must use the spark plugs that your vehicle’s manufacturer recommends even if you need to pay a little more.

 

Final Words

 

Changing your vehicle’s spark plugs at a regular interval is critically important to ensure a better driving experience and engine performance. Depending upon the type of spark plugs your vehicle uses, you’ll need to change them after every 30,000 to 150,000 miles.

 

We hope this guide will help you to make the most informed decisions to keep your spark plugs and vehicle in a good shape.