Can You Spray Carb Cleaner In Spark Plug Hole – Is It Deteriorative?

The stubborn dirt on the carburetors would not go off that easily. That’s why carb cleaner contains several ingredients that are helpful in removing dirt and even act as a solvent.

But can you spray carb cleaner in the Spark Plug hole? Yes. You can use carb cleaner to clean the spark plug hole. The spark plug can develop debris with time. Carb cleaner can dissolve the encrusted areas and fix them. Meanwhile, residues can backfire.

However, spraying carb cleaners in the spark plug can have both benefits and disadvantages. And it all depends on the application of the cleaner. You can get all the details in this article, which will help you get a thorough idea.

Table: Crab Cleaner Ingredients And Their Properties

Let’s get to know the ingredients used in carb cleaners from the table below.

PropaneCombined acts as a cleaner
Do not inhale or swallow the gaseous mixture
Act as the solvent in the cleaner
AcetoneAlso acts as a solvent
Highly flammable
Avoid contact with heat and air
TolueneHelps to remove grease efficiently
Has solvent properties
Methyl ethyl ketoneIs the primary component in the carb cleaner
Avoid contact with the skin
Slowly evaporates with time and influences the cleaning process effectively
2-ButoxyethanolActs as a dissolver
Avoid inhaling and swallowing as it is carcinogenic
XyleneActs to remove stubborn dirt and materials
Dissolves the organic components
Get vaporized easily
EthylbenzeneAn effective chemical solvent
Added with xylene to dissolve components
Avoid contact with skin and eye as can lead to irritation

Can You Spray Carb Cleaner In Spark Plug Hole?

Carb Cleaner

Yes. Carb cleaner can be used to clean the spark plug hole. Be sure to dry it after applying and leave no liquid on the spark plug hole. Otherwise, the residues would get trapped in the spark plug hole and can cause more misfiring. At last, the cleaning can go in vain.

The dirt becomes stubborn with time. Later you might need to change the spark plug if the dirt becomes uncleanable. And all the carb cleaner ingredients combined help clean the dirt on the spark plug.

However, it’s unfortunate that changing the spark plug always does not go well. It can rather make the condition of the vehicle worse. So it would be better if you could clean the spark plug without leaving any dirt.

And if you do not clean the spark plug and the spark plug hole properly, this will only slow down the vehicle with time.

Is Carb Cleaner Safe To Use?

When you use carb cleaner, you must be cautious. All the ingredients used in the carb cleaner are highly toxic; some are also carcinogenic.

  • If you indifferently handle this with your bare hand and inhale it, it can accelerate lung problems. Even followed by breathing difficulties.
  • Also, contact with the skin can lead to irritation.
  • In the case of eyes, there is no need to describe the effect as the eyes are the most sensitive part of the human body.

However, handling any toxic materials would always have an effect on health. You can only try to minimize the effect by following the precautions.

Moreover, anyone has to follow a detailed process of applying the carb cleaner with maintaining the proper precautions. Otherwise, excessive exposure to such a mixture can only be detrimental.

How To Spray Carb Cleaner In Spark Plug and Spark Plug Hole?

Apart from carb cleaner, you can spray other solvents in the spark plug. There are plenty of cleaners used to clean spark plug holes. Well, the application process for all is the same.

Follow the below steps to continue cleaning with carb cleaner.

Step 1: Follow precautions

First, maintain the precautions. Such as wearing gloves, eyewear, mask. Remember, no contact and no inhalation.

Step 2: Remove the spark plug

  • Remove the spark plug with a spark plug socket or any tool, and then clean it. You have to be careful while removing the spark plug from the hole. If you put too much force, the wires can break off. In this case, you can use Wd40 to loosen the spark plugs.
  • Slowly put the socket inside the spark plug hole and slightly place it. As it is magnetic, it can easily pull off the spark plug.
  • Finally, pull it slowly and remove it with the spark plug socket.
  • Now, it’s time to clean the spark plug and the spark plug hole.

Step 3: Clean the spark plug hole

Well, applying the carb cleaner directly after removing it can make the condition of the spark plug worse. As it is obvious, the spark plug remains in the spark plug hole for a long time.

And over time, it takes the dirt and dust and forms an encrusted condition. Now applying the carb cleaner can make the dust adhere more strongly. Resulting in the removal difficulty of the dirt.

To prevent that, you need to brush off the dirt before the application of the carb cleaner. After sweeping off the excess dirt, you can apply the carb cleaner.

Step 4: Apply carb cleaner

  • Place the spark plug in a suitable place. A nice bowl would be suitable.
  • Then spray the carb cleaner over the spark plug. Spray it fully, covering the spark plug, and keep it dipped for 1-2 hours.
  • After that, pull out the spark plug from the carb cleaner. You will see that the liquid has turned into black color. Well, it is due to the dirt.
  • Now, you can again spray the carb cleaner on the spark plug to remove any residues of dirt.
  • Spray the cleaner again if needed, and keep the plug in the cleaner for another 1 hour. 
  • Finally, to properly clean the spark plug, use a brush. As there are round edges, you need to use something thinner, like brush treads, to clean it. A brush would do the rest work.

Now, for cleaning the spark plug hole, you can spray carb cleaner inside the hole. Keep the spraying to a minimal amount. Excessive spraying can leave residues inside. 

  1. After spraying the carb cleaner, let it rest for a few minutes.
  2. Later, you can use the brush or a piece of cloth and swiftly clean the spark plug hole and the residues. 
  3. Gently clean the hole without rubbing.
  4. Blow out the residue with an air gun and let the spark plug hole dry.
  5. After drying, put the spark plug in the spark plug hole. Moreover, you should not put the spark plug back in without drying it.

When To Change The Spark Plug?

Even if you clean the spark plug properly, it does not mean it will do well. The reason is sometimes the spark plug becomes worn out. In that case, changing the spark plug is a better option than cleaning.

Check your car’s spark plug for the following symptoms to get insight into it.

  • If the spark plug gap has increased, make it low.
  • Normally, the gap in the spark plug is kept at 1.1 mm.
  • The gap can get bigger with time. Reduce the gap without breaking the electrode.
  • And also look for the insulator. Sometimes, the insulator can become worn off.

In these cases, changing the spark plug is the wise thing to do. Nevertheless, follow the manual instruction to not cause any damage.


Cleaning the spark plug is possible by applying the carb cleaner. But spraying it in the hole can be a bit risky. You would not be able to drop the residue of the carb cleaner from the spark plug hole.

Instead, blowing air would remove a certain amount of residue. The residues can later make a disturbance during driving. And the purpose of cleaning the carb cleaner is to get rid of noises and make the drive smoother. Thus, you have to be careful while cleaning every part of the vehicle.