Skip to content

How To Clean Spark Plugs With WD40

Spark plugs are an integral part of an automobile’s internal combustion engine and are responsible for igniting the air-fuel mixture. However, over time, the spark plugs may become fouled with dirt and debris, leading to poor engine performance.

Fortunately, you can clean spark plugs with WD40 to restore their performance. So how do you clean spark plugs with WD40?

In general, to clean spark plugs with wd40, you have to remove the spark plugs and spray them with the cleaner. Then, use a wire brush to scrub away any dirt and debris. Finally, reinstall the spark plugs, and your engine will run smoothly again.

In this guide, we will discuss the process for cleaning spark plugs, the materials you will need, and the safety precautions to take when using WD40. Let’s get started!

Why Should You Clean Your Spark Plugs Regularly?

Why Should You Clean Your Spark Plugs Regularly

Cleaning spark plugs with WD40 is a great way to improve engine performance and maintain the longevity of your vehicle. Here are some specific benefits of this process:

1. Reduces Carbon Buildup

Carbon deposits on the spark plugs are one of the main causes of engine misfiring. You can remove these deposits by cleaning them with WD40, thus improving engine performance.

2. Enhances Efficiency

WD40 helps keep the spark plug electrodes clear of debris, which helps the spark plug spread the spark more efficiently. This improves the overall efficiency of the engine.

3. Prevents Corrosion

WD40 prevents corrosion on the spark plug electrodes, which can reduce the life of the spark plug.

4. Better Mileage

Cleaning spark plugs with WD40 leads to better fuel efficiency, resulting in better mileage.

5. Cost Efficient

Cleaning spark plugs with WD40 is a cost-efficient way to maintain the engine. This is because WD40 is relatively cheap and easy to find.

How To Clean Spark Plugs With WD40

WD40 is a multi-purpose lubricant and cleaner that you can use to clean spark plugs, including Iridium Spark plugs. It is a fast and easy way to clean dirty spark plugs and improve engine performance.

How to Clean Spark Plugs With WD40?

Here is a guide on how to clean spark plugs with WD40:

1. Preparation

Before you begin, you will need to gather the necessary supplies. This includes:

  • WD40
  • A rag or brush
  • An extension or spark plug socket
  • An adjustable wrench

2. Removing the Spark Plug

The first step is to remove the spark plug. To do this, use the adjustable wrench to loosen the spark plug. Once it is loose enough, use the extension or spark plug socket to unscrew the spark plug completely.

3. Cleaning the Spark Plug

Once the spark plug is removed, you can begin cleaning it. Spray some WD40 onto a rag or brush, then use it to scrub the outside of the spark plug. Ensure to get into all the nooks and crannies. Wipe away any excess WD40 with a dry rag.

4. Reinstalling the Spark Plug

After cleaning the spark plug, it’s time to reinstall it. Line up the spark plug with the thread in the cylinder. Use the extension or spark plug socket to screw it back in. However, ensure it is tight, but not too tight, before continuing.

Other Ways To Clean Spark Plugs

Apart from using WD40, there are some other ways to clean your spark plugs. Here we have discussed some such methods.

1. Sandblasting

Sandblasting is a great way to remove carbon deposits from spark plugs. It involves blasting the plug with special sand, which breaks down the deposits. This method is quick, effective, and often used in professional auto shops.

2. Chemical Cleaners

Chemical cleaners are another way to get rid of carbon deposits on spark plugs. These cleaners are sprayed onto the spark plugs and can quickly break down carbon buildup. Chemical cleaners are typically more expensive than sandblasting and require more time and effort to use.

How To Tell If Your Spark Plugs Are Clean

If your vehicle is running poorly or the fuel efficiency has decreased, it may be time to check your spark plugs. Spark plugs can become dirty from a build-up of carbon and oil deposits, which can reduce the performance of your engine and lead to other problems.

Here are a few ways to tell if your spark plugs are dirty and need to be replaced:

How to Tell If Your Spark Plugs Are Clean

  1. Check the Spark Plug Wires: If your spark plug wires appear to be frayed, cracked, or corroded, they may be in need of replacement. This could indicate that the spark plugs are dirty and need to be replaced.
  2. Check the Color of the Plug: A clean spark plug should be light gray or tan. If it appears to be black or covered in debris, it is likely that the spark plug is dirty and needs to be replaced.
  3. Check the Gap: The gap in the spark plug should be consistent and even. It could indicate that the spark plug is dirty and needs to be replaced if it is too wide or too narrow.
  4. Check for Fouling: If the spark plug is covered in oil or debris, it likely needs to be replaced. This is a sign that the spark plug is not burning the fuel efficiently and needs to be replaced.

Potential Problems With Cleaning Spark Plugs with WD40

Improper use of this product can potentially cause significant damage to the spark plugs, resulting in costly repairs and lost engine performance. Here we’ve discussed the potential problems that can arise when cleaning spark plugs with WD40.

1. Corrosion and Wear

One of the main issues with using WD40 to clean spark plugs is that it can cause corrosion and wear over time. WD40 is a water-displacing lubricant, leaving behind a thin layer of residue on the spark plug that can corrode the metal over time.

This can cause the plug to become worn and less effective at transferring the spark needed for proper engine performance.

2. Damage to the Insulator

The insulator of the spark plug is a thin ceramic material that helps insulate the plug from the engine’s heat. WD40 can potentially damage this material, resulting in cracks and other damage that can lead to misfires and other problems.

Additionally, the WD40 residue can also build up on the insulator, reducing its ability to insulate the plug and causing further damage.

3. Inappropriate Use of Chemical Cleaners

WD40 is also not designed to be used as a chemical cleaner, so using it to clean spark plugs can potentially cause more damage than it prevents.

Chemical cleaners are specifically designed to remove deposits and contaminants from spark plugs. Thus, using WD40 can potentially cause them to become clogged with residue and reduce their efficiency.

Tips and Safety Precautions When Cleaning Spark Plugs with WD40

Cleaning spark plugs is a crucial part of regular car maintenance. Doing so helps to ensure the car runs smoothly and efficiently. When cleaning spark plugs, take certain steps to ensure the job is done safely and correctly.

Here are some safety precautions to consider when cleaning spark plugs with WD40:

  1. Always wear safety goggles when spraying around electrical components and spark plugs.
  2. Ensure the area around the spark plugs is clear of combustible materials, such as gasoline or oil.
  3. Unplug the spark plug wires before applying WD40 and Spray the spark plugs in a well-ventilated area.
  4. Avoid spraying too much WD40 onto the spark plugs. A light mist is all that is needed.
  5. Allow the WD40 to sit for a few minutes before wiping it off with a clean cloth.


As you’ve seen, learning how to clean spark plugs with WD40 is a simple and effective way to ensure that your spark plugs are functioning properly and efficiently. By following the steps outlined in this article, you can ensure that you maintain your spark plugs.

This way, you can ensure your vehicle spark plug is in optimal condition and avoid any problems in the future. However, you should always wear protective gear when cleaning spark plugs and ensure that the area is well-ventilated.