What Causes Spark Plugs to Go Bad Fast [Quick Check]

Your engine will not start if the spark plugs are not working. Spark plugs are designed to transfer an electrical signal from the ignition coil at a set moment, causing the air-fuel combination inside the combustion chamber to ignite.

So even if just one plug fails, the difference in functioning will be evident. Your engine would spit and sputter, it would perform scratchily, it would idle poorly, and it would spit and sputter.

When a spark plug wears out or exhibits signs of failure, regardless of any warranties or promises made by the car manufacturer, forcing you to ask, “what causes spark plugs to go bad fast?”

Quality spark plugs will efficiently burn fuel, but poor or failed spark plugs will cause the motor to not start at all.

What Causes Spark Plugs to Go Bad Fast?

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Spark plugs are critical to ensure your vehicle’s engine functions. They’re in charge of sparking the gas in the cylinder to provide power, and they need to be replaced if your car has covered a couple of thousand miles (about 25,000). Spark plugs, unfortunately, will eventually fail—but why?

Engine Oil

The oil’s passage into the combustion chamber is a significant source of spark plug difficulties. If oil spills into the engine’s combustion chamber, the spark plug’s tip might get greasy, causing it to fail prematurely.

Keep watch over your engine if it starts to burn oil since this could indicate that your spark plugs are damaged and will have a reduced lifespan. A spark plug’s life can be extended by 10% when using decent synthetic engine oil.

Leaky Head Gasket

Spark plug fouling can also be caused by coolant seeping into the combustion chamber. This is a major issue since repairing a leaking head gasket can be extremely costly.

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A snubbed spark plug could indicate that a head gasket is leaking and should be replaced immediately.


Overheating the spark plug tip repeatedly might cause the plug to deteriorate prematurely. This can be caused by various factors:

  1. Pre-ignition – this might result in a build-up of heat in the combustion chamber.
  2. A faulty cooling system – may lead the engine and spark plugs to overheat, leading the electrodes in the spark plugs to wear out more quickly.

Excess heat accumulation can harm the spark plug if the engine timing is incorrect and there is pre-ignition.

Poor Fuel Quality

The substance inside a low-quality gasoline filter degrades over time, allowing impurities to enter your engine through the intake manifold when it’s idle and the exhaust system when it’s running. This will create further stress on the inside of the spark plug and erode some of the insulators.

Oil and Carbon Buildup

The accumulation of oil, carbon and combustion byproducts is the most prevalent cause of spark plug failure. Anti-corrosion coatings are included in spark plugs to help protect engine components from corrosion over time.

Some pollutants, such as lead or copper bits from deteriorating valve seats, are also included. A carbon-fouled spark plug has black, dried soot on the electrodes and insulator tip.

Carbon accumulation shortens the longevity of a spark plug, resulting in hard starts, lower acceleration, engine misfires, and the appearance of the check engine light.

The following are some of the causes of a carbon-fouling spark plug:

  • A clogged air filter
  • Clogged fuel injectors
  • Driving at excessively low speeds
  • A fuel/air mixture that is overly rich
  • Leaving your vehicle idle too long

Using Leaded Gas

Another typical reason for a spark plug failure is leaded fuel, which introduces lead particles into the engine and deposits it on components such as valves and piston rings. This buildup of lead will eventually find its way into the spark plug.

Subpar Fuel Filters

Fuel filters that aren’t working properly can potentially be a problem. Spark plugs that go faulty quickly can also be caused by defective fuel filters.

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The gasoline filter protects the engine by filtering grime, rust particles, and other impurities out of it.

Also, the performance of your spark plugs can be harmed if your vehicle’s air intake system is subjected to excess dirt or foreign objects in the gas.

When you’ve had enough exposure to low-quality gasoline filters, the spark plug may also go bad quickly.

Loose Wires

Failing spark plugs are usually caused by faulty wire connection, low-quality plugs, or incorrect engine tuning. Before you drive your automobile, make sure it’s tuned up and that all cables are in good working order.

Before changing any spark plug-related equipment, ensure your automobile is tuned properly and that all wires are in good working order.

In addition, to avoid premature wear, ensure you have only quality spark plugs. Check out the tell-tale signs of loose spark plugs from this article.

Incorrect Spark Plug Gap

To guarantee optimal engine performance, the spacing between the central and outer electrodes of the spark plug must be precisely regulated.

The proper gap guarantees that the arcing takes place at the correct voltage to kindle the gas and produce the combustion that allows the engine to run.

If the gap isn’t set correctly, the spark plug tip may be subjected to additional stress, causing it to deteriorate and wear down prematurely.

When the spark plug is inserted, the components on the tip have a little gap that must be calculated precisely for your engine. If this gap is incorrect, extra stress might be placed on the tip, causing it to wear out more quickly.

Not Paying Attention to Spark Plugs  

If the spark plugs are very old, they must be replaced as well. A sparkplug’s lifespan varies based on driving circumstances and engine type, but it’s normally safe to replace them if your car has traveled about 30,000 miles or every three years. You can also learn about the signs and symptoms of bad spark plugs.

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Frequently Asked Questions (FAQs):

How quickly can spark plugs fail? (40-50 words)

Spark plugs can last for up to 80,000 miles before they need to be replaced. However, if you see any of the warning indications listed above, it’s time to replace your spark plugs. So, ideally, have them changed every 20,000 miles traveled, on average.

How do I know if my spark plugs need to be replaced?

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There are a few indicators that your spark plugs need to be replaced, such as.

  • Misfiring
  • Running roughly
  • Delays in acceleration
  • The car is difficult to start
  • Check engine light is up
  • The engine is extremely noisy

How to prevent spark plugs from turning black?

Spark plugs must be polished and maintained regularly in order for your car to operate effectively. Failing to do this causes the plugs to eventually turn black.

Before setting off, ensure the spark plugs are cleaned with paper towels to remove all of the dirt and oil. If the engine has been on for some time, disconnect your spark plugs and grab a hard brush or some steel wool, apply oil lightly, and clean it up. Here’s a blog on how to clean a fouled spark plug.

This will not only remove any black residue from the inside, but it will also improve performance by ensuring that all surfaces are evenly coated, allowing optimum combustion to occur.

What happens if you have a bad spark plug?

When spark plugs fail, they emit a nasty odor from the exhaust. When partial combustion occurs, unprocessed fuel will likely go into the exhaust, giving in a rotten egg or sulfur odor.

Will a bad spark plug stop my car from starting?

As you may know, bad spark plugs can result in engine misfiring or an unbalanced air/fuel mixture. Driving with a misfire is extremely risky since it might destroy your engine.

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If you have a defective spark plug and are driving, your engine may not work properly.

When trying to accelerate quickly from a stoplight, this might cause issues such as misfires or hard starts, both of which are symptoms that something is amiss.

Why are my spark plugs always burning out?

The fact that your spark plugs are covered in gas or gasoline is the cause of their frequent failure. When this happens, a leak occurs, causing those priceless little sparks to fly off at the touch of a finger.

Overheating and blisters on the ceramic around the center electrode may occur if the tip temperature exceeds 850°C.

This might result in meltdowns and subsequent pre-ignition/detonation, which will undoubtedly harm your engine.

Why are my spark plugs wet?

YouTube video

In this video, Peter discusses what causes wet spark plugs and what could be wrong with your car engine. You’ll also get to hear what sounds your engine makes when the plugs are wet.

To understand the problem, you’ll get a close-up of where the moisture is coming from as he helps you take a look at your radiator.

He’ll also guide you on how the head gasket leak leads to moist plugs.

In a detailed description, you’ll get to learn about the road from the radiator and how the radiator liquid and coolant travel to the cylinder tubes.

What destroys a spark plug?

Spark plugs eventually suffer wear and tear due to several factors, including:

  • Carbon fouling
  • Leaky head gasket
  • Engine overheating
  • Bad gasoline filters can cause congestion and deterioration to the plug’s tip
  • Wet spark plugs short-circuit instead of passing the electricity across the electrode gap
  • Inappropriate spark plugs gap, placing extra stress on the tip, causing it to wear out faster
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Can you use a spark plug tester to check if it is bad?

Yes, you can. Just follow this simple process:

  1. Connect the ignition wire to a spark plug tester. The tester attaches to the spark plug in your engine on the other end.
  2. Turn the key in the ignition, and bring the engine to life. If it doesn’t start immediately, then turn it over and keep an eye on the see-through sides of the tester.

If there is no visible light or glow, you can be certain that no spark is occurring at the crucial tip of the spark plug. While this isn’t a sure sign that the plug is faulty, it could show that there’s some damage.

What causes a spark plug to crack?

Corrosion may result in defective sparks, especially in older autos with excessive usage, causing the plugs to crack. You’ll notice a rattling sound while moving and slowly accelerating due to this, among other things.

Going Bad Too Fast?

Now that you know what causes spark plugs to go bad fast, you can take better care of your car. If you want to keep your spark plugs from rusting, you should regularly maintain them and use the proper fuel.

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