What Causes Spark Plugs To Go Bad and How Can You Fix It?

What causes spark plugs to go bad?” is a common question asked by many automobile users, and the main reason is faulty fuel filters. Spark plugs are essential components of an engine because they give a spark that gives the power to turn the engine pistons.

What Causes Spark Plugs To Go Bad

However, these components tend to go bad fast, and it is essential to know how to fix the issue. This article will discuss why they go bad, how you can fix them, and other essential things to know.

What Makes Vehicle Spark Plugs Go Bad?

The factors that make vehicle spark plugs go bad include a build-up of carbon and oil, poor fuel quality, and the use of leaded gasoline. Your car’s spark plug may also go bad quickly if the wire connections are loose, if there is overheating, and much more.

The harm a faulty spark plug can cause is it can make it difficult to start your engine. Every owner of a gasoline-powered vehicle is familiar with the routine. This is why generally, around 30,000 miles or so, the spark plugs must be replaced.

– Faulty Fuel Filters

Bad fuel filters could be the root cause of spark plug failure. The gasoline filter protects the engine by cleaning it of dirt, rust particles, and other impurities. When your car’s air intake system is exposed to too much dirt or foreign objects in the gas, it might compromise the effectiveness of your spark plugs. When you have enough exposure to low-quality gasoline filters, it is possible that the spark plug can go bad quickly.

– Using Bad Gasoline or Engine Oil

Another common cause of a spark plug failure is the use of leaded gasoline. It introduces lead into the engine and deposits it on components such as valves or piston rings. This lead buildup will then enter the spark plug.

The engine oil type and condition also affect how fast your spark plug goes bad. High-quality synthetic engine oil can increase the lifespan of a spark plug by 10 percent.

– Carbon and Oil Build Up

The most common reason for a spark plug failure is the accumulation of oil, carbon, and combustion byproducts. Spark plugs have an anti-corrosion coating that helps protect them from engine components that can damage them over time.

It also includes pollutants such as lead or copper particles from worn valve seats. However, these coatings are not impermeable and will eventually wear down and shatter due to the buildup of oil, carbon, and combustion byproducts.

– Low Fuel Quality

Spark plugs might also go bad fast due to poor fuel quality. This is because the material inside a low-quality fuel filter doesn’t last long and contains more impurities, entering your engine through the intake manifold while idling and the exhaust system when running. When this poor fuel quality enters your engine, it causes additional wear on the interior of a spark plug and can even begin to erode some of the insulators.

Why Spark Plugs To Go Bad

This causes electrical shorts, which cause sparks to fly everywhere instead of just where they need to be for the ignition. This will cause a misfire and your engine’s timing to be off, which could be better for performance and gas consumption.

– Slack Wire Connection

A faulty wire connection, low-quality plugs, or poor engine tuning usually cause spark plug failure. Before changing any spark plug-related parts and equipment, ensure your automobile is tuned correctly and all wires are in good working order. Furthermore, to avoid premature wear, only use high-quality spark plugs.

– Leaking Head Gasket

Leaking coolant into the combustion chamber can also cause spark plug fouling. This is a major problem since repairing a leaking head gasket can be extremely costly. A clogged spark plug may indicate that a head gasket leaks and should be repaired quickly.

– Wrong Spark Plugs and Overheating

When installing the spark plug, the metals on the tip have a little gap that must be precisely calculated for your engine. Extra stress might be placed on the end if the gap is not correct, causing it to wear out faster. This is one of the reasons the spark plugs may fail quickly.

Overheating of the spark plug end can cause it to wear out prematurely. Several factors can cause this. For example, if the engine timing is incorrect and pre-ignition occurs, this can cause excessive heat buildup in the combustion chamber, affecting the spark plug.

If your mechanic claims to use “laser” technology for removing and changing spark plugs in current automobiles, insist on ordinary plugs being reinstalled. Otherwise, you risk breaking a plug off your cylinder head, which is a costly problem, especially if your warranty expires soon.

Wrong Spark Plugs

However, the reason modern vehicles can go so long without tune-ups has nothing to do with spark plugs. It all comes down to fuel injection and engine management computers, which today control the fuel/air combination more precisely than ever.

– Failing To Inspect Your Spark Plugs

If the spark plugs are too old, they must be replaced as well. A sparkplug’s whole lifespan varies based on driving circumstances and engine make, but replacing them every 30,000 miles or three years is usually safe. It is crucial to note that spark plugs should not be replaced.

Nonetheless, if you see any signs of wear or degradation, it is time to replace them.The two most essential elements in determining how long a spark plug will endure before needing to be replaced are:

  • Fuel quality and condition: If you use high-octane fuel, your spark plugs will last about three months longer before they need replacement.
  • Engine oil type and condition

Too much fuel or air in your engine may also result in higher cylinder pressure, which hastens electrode deterioration. Spark plugs may also operate more quickly and prematurely than intended if you operate your vehicle beyond one mile above sea level. An example is Colorado’s “The Pikes Peak,” as atmospheric factors such as air density do not affect their voltage.

How To Prevent Your Spark Plug From Going Bad?

To prevent your spark plug from going bad, you should use the correct spark plug for your vehicle, use high-quality components, always maintain a clean engine, not leave the engine running idle, change spark plugs regularly, and avoid overloading your vehicle. The following are some precautions you should take to keep your spark plugs from going bad too quickly:

– Use the Correct Spark Plug

It’s essential to use suitable spark plugs for your car. Misfires from incorrect spark plugs might result in premature spark plug wear. To determine which spark plug type is best for your car, consult the owner’s manual or a reliable mechanic.

The kind of spark plug you should choose are those made from iridium. They have been proven to be one of the most durable spark plugs. It provides outstanding dependability, fuel efficiency, durability and performance. These spark plugs have longer lifespans than platinum and copper options.

– Always Clean Your Engine

Your spark plugs may malfunction in a dirty engine, resulting in accelerated wear. Keeping your engine clean regularly and changing the air filter as needed help to lessen the likelihood of this happening. Be careful to routinely check the oil level in your engine and replace it in accordance with the manufacturer’s instructions.

– Don’t Leave Your Engine Idle

Your engine will not run at its best temperature when idle, which might lead to spark plug fouling. If you frequently idle in stop-and-go traffic, this is especially true. Turn off the engine if you’re going to be sitting still for a while. This will not only help your spark plugs last longer, but it will also lessen unwanted emissions.

– Change Spark Plugs Regularly

Even though your spark plugs seem to be in fine shape, you should still replace them per the manufacturer’s instructions. Depending on the make and type of your car, this can vary. Regular spark plug replacement will ensure optimum engine performance and avert more expensive future repairs.

Solutions of Spark Plugs To Go Bad

You should replace your spark plugs every 20,000 miles. Some manufacturers advise replacing them after 30,000 miles (45,000 kilometers). A physical indication that your vehicle spark plug needs to be replaced soon is when you find that it becomes much too hot.

You should also change it when the insulation layer explodes on the wire, resulting in a short. Also, when inspecting the spark plugs in your car, look for physical damage. Examine the electrodes for physical evidence of the damage, such as cracks or missing parts. If they are damaged, you may need to replace them.

– Avoid Overloading Your Vehicle

When your car is overloaded, the engine has to work harder, which might result in spark plugs wearing out faster than they should. Make sure you are not driving a vehicle that cannot handle the weight you are carrying. This is crucial if you routinely haul large loads or navigate challenging terrain.

Other things to note are:

  • Change spark plugs once every 30,000 miles or less, depending on your vehicle. A loose wire connection frequently results in a misfire, leading to clogged spark plug holes in the head and causing hot spots on the platinum.
  • Use a set of spark plugs made specifically for your engine. Using low-quality plugs will cause them to wear out faster, so invest in high-quality ones.
  • To prevent power shocks from harming computer components such as ECUs or other wiring, disconnect the negative car battery wire and wait at least 30 minutes before performing any maintenance on the vehicle.

These recommendations can help you maintain a healthy engine and make your spark plugs last longer. Always remember to refer to your vehicle’s owner’s manual and a reliable mechanic for detailed instructions on spark plug maintenance.


– What Should You Do if You Notice Bad Spark Plug Symptoms?

If you notice bad spark plug symptoms, you need to remove the ignition coils and cord and anything covering them. However, the technique is determined by the model of your vehicle. Some models are straightforward to replace, while others require more knowledge.

Some V-engine versions have difficult-to-reach spark plugs. You may gain access to numerous engine components. To replace the spark plug, however, all car models will follow the same technique, and they include the following:

    1. Remove all the ignition cords and coins and any other thing that may be covering the ignition coils or wiring.
    2. All broken spark plugs should be replaced with high-quality replacements.
    3. Check the lengths of your sparks to be sure you’ve got the right ones. Spark plugs that are excessively lengthy can cause piston damage.
    4. Threads should be lubricated and tightened with a torque wrench.
    5. All equipment removed, including the ignition cables and coils, must be returned.

What Causes Spark Plugs To Go Bad Details


You already know what could make your spark plug go bad quickly, as we have already discussed everything you need to know in this article.

Let’s have a quick rundown of some of the essential points.

  • Spark plugs may go bad prematurely if you use fuel or gasoline with poor quality, if there are loose wire connections, if your vehicle is overheating, if there are bad fuel filters, etc.
  • Remember to change spark plugs every 30,000 miles or less, using a set of spark plugs made specifically for your engine. Also, disconnect the negative battery wire and wait at least 30 minutes before performing any maintenance on your vehicle.
  • If you notice spark plug symptoms, you need to remove the ignition coils and cord and anything covering them.
  • You should replace your spark plugs every 20,000 miles. Some manufacturers advise replacing them after 30,000 miles (45,000 kilometers).
  • Spark plugs made with iridium have been proven to be one of the most durable options, providing the ideal dependability, fuel efficiency, durability, and performance.

Make an appointment with your mechanic for a spark plug failure analysis if your spark plugs are failing quickly or your vehicle is experiencing another type of problem.

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