Updated at: 19-03-2022 - By: micdot

This article contains affiliate links. Using any of the links on this page will allow me to earn a small commission at no additional cost to you.If you’re always having to replace your car’s spark plugs, you may be wondering what’s causing this and what you can do to prevent it.

So, what causes spark plugs to fail quickly is a combination of the electrode gap being smaller with time and the lack of voltage at the plug tip for ionization. We’ll go through some more potential causes of your spark plugs breaking more frequently than is necessary in today’s post. To begin with, we need to know what a spark plug is in the first place.

What Are Spark Plugs?

Small metal pieces that sit in the engine of an automobile and emit an electric current are known as spark plugs. To generate kinetic energy, the fuel in the automobile is ignited and mixed with oxygen. It is the job of the spark plug to ensure that gasoline combusts and travels via the air intake manifold to each cylinder of the engine. Every time you start your car, a process known as the spark ignition cycle occurs. Before installing new spark plugs, make sure your vehicle’s spark plugs are correctly connected to the distributor cap and coil by running them for at least 15 minutes in an oxygen-free electric environment.

It is possible for the spark plug to force hot gas out of a cylinder and produce an engine misfire when these two components are not connected. A new set of spark plugs or a rewiring of the distributor cap may be necessary in the event that this occurs frequently enough.

What Happens When Spark Plugs Go Bad?

When a spark plug breaks or begins to malfunction, other parts of the engine begin to malfunction as well. The vehicle may misfire or be difficult to start on many occasions. If you own a car, you should know when to replace these parts because they can cause significant harm if left ignored.

What Causes Spark Plugs To Go Bad Fast?

A spark plug can quickly go bad for a variety of reasons, some of which are listed below:

1. Build of oil and carbon

The accumulation of oil, carbon, and other combustion byproducts is the most prevalent cause of spark plug failure. A special anti-corrosion coating is applied to spark plugs to assist keep them from corroding in the engine. Some pollutants, such as lead or copper particles from worn valve seats, are included here as well.

Although these coatings are impermeable, they will eventually wear and crack due to the accumulation of oil, carbon, and combustion byproducts on them.

2. Use of leaded gasoline

Lead can accumulate on engine parts such as valves and piston rings as a result of the usage of leaded gasoline in an automobile. The lead buildup will eventually find its way into the spark plug and cause a fire..

3. Poor fuel quality

It is possible for spark plugs to fail fast if the fuel is of poor quality. There are more impurities in a lower grade filter, which means that they can enter your engine through both the intake manifold and exhaust system when you’re idling and running, respectively. As a result of poor fuel quality, your engine’s spark plugs are going to wear out more quickly than they should, and some of the insulators may even begin to dissolve.

Sparks fly all over the place, rather than just where they’re needed for ignition, as a result of these electrical shorts. As a result, your engine’s timing may be out of whack, which is terrible for performance and gas consumption.

4 Bad fuel filters

Spark plugs that fail prematurely can be caused by a variety of factors, including dirty fuel filters. Protects the engine from dirt, rust particles, and other impurities with the help of the fuel filter. The performance of your spark plugs can be harmed if the air intake system of your car is subjected to excessive amounts of dirt or foreign objects in the gas.

It’s possible that your spark plug will fail quickly if you’ve been exposed to poor quality gasoline filters for a long period of time.

5. Loose wire connection

Spark plug failure might be the result of a faulty wire connection, a poor-quality plug, or even an engine that has been improperly tuned. Before replacing any equipment related to spark plugs, make sure your automobile is well-tuned and that all wiring are in good working order. In addition, to avoid premature wear, only use high-quality spark plugs.

6. Overheating

In essence, early wear can be caused by an overheated spark plug tip. There are numerous reasons for this. Engine timing can have an impact on how much heat builds up in the combustion chamber if pre-ignition occurs, which can have an impact on the spark plug as well.

7. Inappropriate spark plugs gap

The space between the metals on the tip of the spark plug must be correctly measured for your engine when it is installed. As a result, the tip will wear down more quickly if the gap is incorrect. This is a possible explanation why the spark plugs may wear out so quickly.

8. Leaky head gasket

Spark plug fouling can also be caused by coolant leaking into the combustion chamber. A leaky head gasket is a huge problem since it can cost a lot of money to correct. Head gaskets might begin to leak when a spark plug becomes fouled.

9. Type of engine oil

The type and condition of the engine oil that is being used. A spark plug’s lifespan can be extended by 10% by using a high-quality synthetic engine oil.

10. Paying no attention to your spark plugs

Used spark plug. Spark plug of the car after 100000 km of run. Close up

There are times when spark plugs need to be replaced. In general, a sparkplug should be replaced every 30,000 miles or three years based on driving circumstances and the manufacturer of the engine (whichever comes first). If you see any signs of wear or degeneration, it is time to replace your spark plugs. This is not something you should do just because you can. How long a spark plug lasts before it needs to be replaced is determined by the following factors: 

Your fuel’s purity and cleanliness. Use high-octane gasoline to extend the life of your spark plugs by about three months.

The type and condition of the engine oil that is being used. The lifespan of a spark plug can be increased by 10% with the use of high-quality synthetic engine oil. As a result, if your engine has too much air or fuel, the cylinder pressure will increase, which will wear down the electrodes much more quickly. If you’re driving at an altitude of more than a mile above sea level, such as on “The Pikes Peak” in Colorado, your car’s spark plugs may go faster and earlier than expected because meteorological variables, such as air density, cannot influence their voltage.

How to Prevent Spark Plug Failure

Preventative actions to prolong the life of your spark plugs include the following:
Keep the engine tuned to the correct specifications. Premature replacement of plugs and wires can be avoided in this way. Depending on your car, you should replace the spark plugs every 30,000 miles or less. A misfire is frequently caused by a loose wire connection, which can lead to clogged up spark plug holes in the head, resulting in platinum hot spots. Use the correct set of spark plugs for your vehicle. Make sure you buy high-quality plugs instead of low-quality ones, which will wear out more quickly.

Remove the negative battery wire and wait at least 30 minutes before starting any work on the car to prevent power shocks from harming computer components like ECUs or other wiring.

Frequently Asked Questions

How often should I change my spark plugs?

Spark plugs are normally replaced every 20,000 miles. At 30,000 miles or 45,000 kilometers, some manufacturers advise customers to replace their brake pads and discs. A tangible sign that your spark plug needs to be replaced soon is when it becomes too hot and the insulating layer on the wire is blown off, resulting in a short circuit.

Make sure to inspect your car’s spark plugs for physical damage as well. Inspect the electrodes for any evidence of physical damage, such as cracks or missing sections. In the event that they show signs of wear and tear, you may need to replace them.

How fast can spark plugs go bad?

Spark plugs typically last 80,000 miles before they need to be replaced. However, if you see any of the warning indications listed above, you should have your spark plugs checked out.

Can spark plugs suddenly go bad?

It’s true that a good spark plug might suddenly fail and stop working.

How do I know if my spark plugs need changing?

If your car is difficult to start, your “check engine” light is on, your engine is extremely loud, or any of these symptoms apply to you, it may be time to replace your spark plugs.

What is the longest lasting spark plug?

One of the most long-lasting spark plugs is NGK 6619 Iridium IX Spark Plugs. If you want to get the most out of your vehicle while saving money on gas, this is the vehicle for you! The iridium structure of these spark plugs ensures a substantially longer lifespan than that of platinum or copper counterparts.

Do spark plugs smell when going bad?

When they’re bad, spark plugs do emit an unpleasant odor from the exhaust. When incomplete combustion occurs, raw fuel enters the exhaust and gives out an odor comparable to rotten eggs or sulfur. There is the possibility that a spark plug is malfunctioning.

Can I drive with a missing spark plug?

An engine misfire or an unbalanced mixing of air and fuel can be caused by faulty spark plugs, as you may be aware. The engine can be damaged if you drive with a misfire.


There are many reasons why spark plugs fail so quickly, and we’ve already covered all of them in this post. When spark plugs fail quickly, or if you’re having other problems with your automobile, make an appointment with your technician right once.