How To Remove a Broken Spark Plug? (Easy 5 Step Guide)

Want to learn how to remove a broken spark plug? We've got your back!

In this guide, you'll learn:

  • What you need to know about removing a broken spark plug
  • How to access spark plugs
  • Supplies you'll need to remove a broken spark plug

And much more!

How to Remove a Broken Spark Plug

Does this sound familiar: You go to remove your spark plug, and SNAP! 

It breaks off into two pieces leaving you with the terminal and nut half of the plug, and the threaded portion with the electrode tip is very much still installed into the cylinder head leaving you with not a lot to grab on to.

Don't worry! You're not the first person this has happened to. Bolts break sometimes! That's just part of working on engines. And when they do, it's nice to have a tap and die set, a nice hand drill, a screw extractor set, and a positive attitude.

So, before you do remove a broken spark plug, I recommend you read this guide for broken spark plug removal to help you in your first-time adventures of handling the business. 

Want to know how to take a broken spark plug out? Keep reading to learn the 5 essential steps to do it yourself!

What You Need To Know About Removing a Broken Spark Plug

The first thing you are going to need is patience. So sit back, crack open your favorite beverage and take a few deep breaths; rushing through this is not going to help. This isn't that hard, but first, you need access to the plugs. 

Accessing the Spark Plugs

Accessing the spark plugs in your engine is easy. Start by removing the high-tension leads that provide electricity to your plugs. This will consist of either tugging on a spark plug cable with pliers(hands) or removing the coil pack bolts with the appropriate socket or screwdriver.

You may also have to take off some sort of air hose that goes to the intake. Youtube is your best friend when it comes time to repair as there are countless DYI videos for each specific vehicle. 

Purchase New Spark Plugs

When doing an engine tune-up, you may have to install new plugs. That's just a basic part of car maintenance. 

Just to give you a good idea, copper plugs should be replaced every 20 thousand miles while platinum and iridium plug every 60-100 thousand. 

A lot of professional mechanics replace the plugs no matter what even if they aren't brand new to ensure the best results on their engine repair. Besides, if you're going to work on an engine you might as well replace cheap parts while you have access to them. 

Use your best judgment based on how many miles you think the spark plugs have on them.  

Supplies You’ll Need For Removing a Broken Spark Plug

Removing a broken plug requires a few more tools than is necessary for simple removing one, so if you aren't committed to doing your engine work yourself it may be a wiser decision to take your engine into a shop. Here are some tools/items you might need:

  • Hand drill
  • Penetrating oil/Pb blaster
  • Ratchet
  • Anti-seize
  • Pb Blaster
  • Breaker bar
  • Screwdriver
  • Easy out extractor 
  • Pliers
  • Flashlight
Did you know: If you notice your spark plug's tip is blackened, this indicates that they've been running with too much fuel.

How To Remove a Broken Spark Plug (5 Step Guide)

  1. Identify the problem by using a flashlight
  2. Install an easy out
  3. Slowly remove the broken portion
  4. Re-thread if necessary
  5. Reinstall spark plug

Step 1: Identify the Problem by Using a Flashlight

The first thing you are going to want to do in any car repair situation is to shine a flashlight on it to get a good idea of what you are dealing with. 

You are most likely going to see a hollowed-out threaded portion of the spark plug still in the cylinder head. 

If there is for some reason isn't enough space to fit an easy out, then you can use a drill bit that is smaller in size to make a small hole. 

Note: To avoid damaging the piston it is wise to crank the engine until the affected piston is in the bottom dead center position and out of harm's way.

Step 2: Install an Easy Out Extractor

Pour some penetrating oil down into the spark plug, and let it sit for a few minutes. Now would be the time to pull out a spiral cut or square cut easy out and a bi-hex 12 point socket to drive the square end of the easy out. 

Install the easy out into the spark plug hole at a straight shot. Lightly tap the extractor into the hole with a hammer. 

Be extra careful not to break the easy out. Doing so will most likely result in having to pull the cylinder head for a machine shop to handle the issue. 

Note: When using a spiral cut extractor, make sure to use a size that is only slightly larger than the hole you're working with. A spiral cut extractor that is too large could cause the spark plug shell to expand which can make things a bit more difficult. 

Step 3: Slowly Remove the Broken Portion

Attach the socket wrench to the easy out, and slowly turn it in the counter-clockwise direction. You will know after a few turns whether or not it's going to work because the extractor will grab the threads and start to turn them.

It might be hard to turn the easy out with just a socket wrench, so you might need to bust out a breaker bar for some better leverage.

If the threads turn, and the broken threaded portion of the spark plug comes out, then that's excellent news! You've just completed the task. You can now blow it out with air and put a new spark plug down into the hole to see if it threads correctly. 

Threads come loose with a little bit of heat. Remember that you can use a heat torch if the plug is stuck, but be careful not to get the cylinder head too hot.

Step 4: Re-Thread Plug Hole If Necessary

If the threads have been destroyed upon removing the old spark plug, then you are going to have to re-thread the hole in the cylinder head with a tap to accommodate the new spark plug. To do this, you are going to want to first blow out the hole with an air compressor attachment. 

Then, pour in some more penetrating oil to make things easier. Use the appropriate tap for the threads on the spark plug. 

An easy way to identify which tap you need is by threading the spark plug into the correct die because it will thread in flawlessly. You can even buy spark plug thread repair kits that likely have exactly what you need for the job if you don't already have a tap and die set. 

Step 5: Reinstall New Spark Plug

Clean the spark plug hole out with compressed air one more time. Apply anti-seize to the threads of the new spark plug(if you wish), gap it properly, and thread it carefully into the new hole by hand. Torque the new spark plug with a torque wrench to avoid the recurring problem of a broken plug. You are now ready to reinstall the plug boot or ignition coil back into place and fire the engine up. 

Other Valuable Resources on Removing a Broken Spark Plug

Still having difficulties?

Don't be afraid to let a trained professional handle the problem. 

Performing your engine repairs is easy with the right tools and confidence, but it does have it's frustrating times when nothing seems to be going the right way. 

Giving your engine a tune-up consists of more than just changing out your old and corroded parts for new spark plugs.

For example, you could remove and clean your fuel injectors, replace your distributor cap and rotor(on older carbureted vehicles) replace the air filter, change the ignition coils, and more for maximum performance and fuel-efficiency.

What if the easy-out extractor breaks? 

Let's be honest, nothing ever goes as planned when working on an engine. So what happens when you break the easy-out and it gets stuck down in the hole? You're going to have to get creative on this one. 

You could try using a solid carbide bur bit on a Dremel to grind it out, or you could even use a skinny drill bit to drill holes around the extractor to loosen it up.

Don't forget to use a torch if you feel appropriate, but don't melt your cylinder head off! Just heat it to a couple of hundred degrees to work with a softer metal.

It is said that you can remove an easy-out extractor with EDM (electrical discharge machining) in the most complex of cases; there's always a solution to your engine problem.

You're going to need luck and skill when removing a broken spark plug. You've got this. Good luck!

Read More >> What Size Socket to Use For a Spark Plug?

About Your Mechanic

About Ryan Nichols

Ryan here! My pro mechanic career began as a technician for Mercedes-Benz. After two years of that great experience, I went out on my own in both the automotive and construction fields. I've since pulled my share of salvage yard parts and fixed more vehicles than I can count.

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