How To Remove Spark Plugs That Are Stuck?

It is a problem when you detect a faulty spark plug but cannot remove it because the plug is stuck. The only option is to remove them by all means because the car’s engine performance will drop due to one or more faulty plugs. So, how do you remove spark plugs that are stuck?

Using force can damage other parts of the engine. However, it is best to learn how to remove stuck plugs instead of forcing them.

How To Remove Stuck Spark Plugs

The following steps cover how to remove a stuck spark plug.How To Remove Stuck Spark Plugs

Step 1. Locate The Plugs

To begin, you must locate the plugs. It is easier to access the front spark plugs than those at the rear. However, the spark plugs are in the same location in some vehicles, just above the engine block.

Some models require you to remove specific components and covers to access them. For example, removing the electrical connector at the top of 7.3 Powerstroke is necessary to access the glow plugs. However, in most car models, you will need to remove the wiper tray to reach the spark plugs.

Step 2. Identify the stuck plugs

It would help if you tried using a spanner to loosen the plugs, to know which of them is stuck. Take note of the stuck plugs because you may need to examine the combustion chamber in the cylinder head. You may find the reason why the plug got stuck in the first place.

Step 3. Apply Penetrating Oil

First, spray some penetrating oil or PB blaster on the stuck spark plug. You may also use a general-purpose lubricant for this purpose.

You may need to spray the penetrating lubricant overnight. Otherwise, leave it for at least 3 hours. In less difficult situations, the lubricant can penetrate for as little as 30 minutes.

Step 4. Loosen the Plugs

Before attempting to loosen the plugs, start your engine briefly to warm it up and allow it to cool.

Starting the engine helps to extract stuck spark plugs. One of the reasons we suggest that is because aluminum expands at high temperatures. As a result, the engine’s heat will create more room for penetrating oil to enter the thread area.

Try to loosen the plug after letting the engine cool down. The stuck spark plugs should come out quickly. Look at them to see if the thread is intact or damaged. You may be able to reuse those plugs after adding lubricant.

Step 5. Clean the Plugs

To remove traces of penetrating oil, spray the threads and seat. Then, air-dry the thread by blowing with compressed air.

Step 6. Install New Plugs

If you remove the old ones, you must install the new ones. Before installing new plugs, use compressed air to clean rust that may be deposited in the ports.

Safety Tips

Before removing the spark plugs:

  1. Allow the engine to cool.
  2. Prepare a fire extinguisher since penetrating oils can ignite if applied to hot surfaces.
  3. Ensure you do not tighten spark plugs more than usual when installing them.

People Also Ask

Can I use WD-40 to remove spark plugs?

It is good to use WD-40 to repel moisture from spark plugs, distributors, batteries, and alternators. Also, if you see traces of rust or corrosion on spark plugs, you can use WD-40 to remove them easily.

How do you remove a seized spark plug from an aluminum head?

This is a prevalent problem people often encounter with spark plugs. The plugs usually get stuck in the aluminum head when removing them from the head.

You will need to use some amount of elbow grease to remove spark plugs stuck in an aluminum head. If you cannot remove the stuck spark plug, you may use penetrating oil, a wrench, or heat. If nothing seems to work, please invite an experienced mechanic to have a look at the problem.

How much does it cost to remove a stuck spark plug?

There is usually a charge of $3– $4 to remove a spark plug that wouldn’t budge. However, this rate may vary from one mechanic to another; please feel free to bargain for a lower bill.


After watching a video tutorial, it may seem easy to remove stuck spark plugs. In reality, there is a lot of attention involved in the process. According to many people, seized spark plugs are challenging to remove at the first attempt. To get it right the first time, you should leave the penetrating oil to soak overnight if you are not in a hurry.

It may take several attempts before the nuts become loose, but it would eventually. Finally, removing seized spark plugs will be a much easier task if you have the proper tools and time.

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