Why Does My Spark Plug Keep Popping Out

Why Does My Spark Plug Keep Popping Out

Imagine you’re driving like usual, and then you realize your car won’t start because the spark plug is repeatedly popping out from under the hood. So, you may wonder, “Why does my spark plug keep popping out?”

If this happens to your car, well, you are not alone. Spark plug tends to pop out for various reasons, like when they are not tightened properly, if there is accumulated dust and rust in spark plugs, and if there is high air pressure built inside due to broken valves. 

It can be any of these. To fix it, you need to inspect your spark plugs and find out the problem.

In this post, we will talk about the problems and tell you how to fix and maintain them properly.

How Spark Plug Works In A Vehicle

The Spark plug Is a crucial component in your vehicle’s ignition system. It is responsible for sparking and igniting the air-fuel mixture in your engine’s combustion system, which helps to create enough power to move your vehicle.

Spark plug works along with different mechanisms. Here is a step by step how spark plug works:

Firstly, The engine’s pistons compress air and fuel inside the combustion chamber, creating high pressure and temperature.

Then the spark plug emits a volt of electricity through a small gap, igniting the air-fuel mixture and creating a controlled explosion.

After that, the explosive force pushes the pistons down, so the power starts to move the vehicle. 

The explosion gas moves out by flowing through the exhaust system, and that’s how spark plugs work in your ignition system.

See Also:

Can A Bad Alternator Cause Engine To Shake?

Why Is Gas Coming Out Of Exhaust Pipe?
Reasons Why Your spark plug keep popping out

Top 4 Reasons Why Spark Plug Wire Keeps Popping Out?

There are several reasons why your spark plug pops out. We will discuss the causes and give solutions to them; here are some of them:

1. Faulty Plug

Well, this is a rare case in which you end up with a faulty plug from your manufacturer. Because manufacturers always run tests on vehicles before dispatching them. In case you do have a plug that pops out of your engine’s distributor. It may be because your spark plug is faulty and doesn’t match your engine’s distributor.

When the metal piece within the plug is deformed or worn out, it may not securely connect to the coil; as a result, your spark plug will be more prone to pop out often.

Spark plugs that are not functioning properly can lead to various engine issues, such as difficulty in starting the engine, decreased fuel efficiency, rough idling, lack of acceleration, and misfires more often.

Solution: The solution to this problem is to call an auto repair shop and replace the spark plug which is specified for your vehicle.

Poor Air Pressure Management

2. Poor Air Pressure Management

If your spark is more likely to pop more often, it may be due to poor air pressure management in your engine’s ignition. It happens because of the building of the combustion gas’s air pressure. As the engine heats up, the space of air around the plug becomes incapable of containing the air pressure, resulting in the removal of the distributor plug.

Solution: The simplest way to fix this issue is to release the air pressure, which will create more room for combustion gases.

Spark plug not installed properly.

3. The Spark plug is not installed properly.

Your spark is more likely to generate heat because its job is to create a spark. So if the wire and crimp tab is not connected tightly, the heat will flow through the gap and melt the wire jacket, which will loosen the plug and make the plug pop out.

Solution: To stop the wire jacket from melting, you have to install the spark plug properly so that no heat can come through.

Blocked dirt and debris

4. Blocked dirt and debris

If the inside of your spark plug is dirty and blocked, it will pop without any reason because it has build-up dirt inside, which will make the plug pop out.

Solution: The solution for this problem is to clean the plug properly and look if there is access grease around it cause grease helps the plug to slip through.

Preventive measures to stop your engines spark plug from popping out

Preventive measures to stop your engines spark plug from popping out

A spark plug popping out of an engine can be a dangerous situation that can cause damage to the engine and even harm to the driver. Here are some preventive measures to help prevent this from happening:

  1. Proper torque: When installing spark plugs, ensure that they are tightened to the manufacturer’s manual specifications. Over-tightening the plug can cause the spark plug to strip the threads or break, while under-tightening can cause the plug to become loose and pop out.
  2. Thread lubrication: Lubricate the spark plug threads with an anti-seize mixture before installation to stop thread damage and make sure that the spark plug stays in place.
  3. Inspect threads: Before installing the spark plug, inspect the threads in the cylinder head for any damage, wear, or weakening. Damaged threads can cause the spark plug to pop out, so they must be repaired before installation.
  4. Replace spark plugs: Replace the spark plugs on time, as it is suggested by the manufacturer. Worn-out plugs can cause the engine to misfire and put undue stress on the threads, which can lead to popping out.
  5. Use quality spark plugs: Use high-quality spark plugs from a reputed manufacturer. Defective plugs can break or strip the threads, which can lead to popping out.
  6. Using a torque wrench: Using a torque wrench can ensure that the spark plug is tightened with the proper specifications. Tightening the spark plug by hand can result in an unstable fit and popping out.


We have provided information about your question, “Why does my spark plug wire keep popping out?”

As mentioned above, the problem could be in the faulty spark plug size, overheating of the engine, and there might be dirt accumulating in spark plugs.

Based on your inspection, you must fix the issue with the above information. Now you can understand why your park plug keeps popping out and how to fix and maintain them. So anytime your spark plug pops out, you know what to do! 

Similar Posts