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Signs of Bad Spark Plugs


Car startup problems are not something new to car owners. Chances are, you have encountered a situation where your car could not start up. Any mechanic would tell you if your car is experiencing problems when starting up, it could very well be due to worn out spark plugs or the ignition wires.

But what are these spark plugs? And how can you tell the signs of a failing spark plug? It turns out this is not rocket science and any person with a basic understanding of automobiles can comprehend any problems arising from the spark plug. Before we navigate the telltale signs of a worn-out spark plug, what are they?

So, what are spark plugs?

You may have heard of the spark plugs or maybe read about it in your car manual, but probably you don’t understand what it is. Or better yet, you have seen the component, but you don’t have a clue what it’s called. Well, spark plugs are the integrated system for ignition. They are what I would call, the core of the ignition component system.

What is the role of Spark Plugs?

The system receives electric current in high voltage and ignites the fuel/air combination in the combustion. The electric voltage is received from the ignition coils and helps to sustain your car in motion. As long as the pistons of your car engine are in motion, the car continues to rev up while at the same time producing smoother and combined mixture of fuel/air.

What are some of the signs of bad spark plugs?

Without a spark, we would not have cars moving since no fuel would go through combustion. Most automobile companies advise car owners to replace their spark plugs after every 30000 up to 50000 miles. It is imperative to understand some of the signs of failing or worn out spark plugs for replacement by a certified mechanic.

Some of the signs of a failed spark plug include:

High Consumption of Fuel

Spark plugs that function properly ensure minimal emission from your car. This is contrary to worn our spark plugs which increase emission hence reducing your car’s fuel economy because of the incomplete combustion process. Additionally, worn out spark plugs have electrodes that are closed up or expanded. This has a bearing on your cars fuel efficiency.

Problems during Ignition

The spark plugs are the core of the ignition component system that can cause ignition problems especially when they are worn out. Without sparks, the car won’t move since there would not be any combustion process. Spark plugs are usually overlooked especially when your car has ignition problems. This is because they are not top of the mind components we think about whenever we are searching for the problems in starting up a car.

Rough Idling of the Engine

Whenever your car is in a state of no motion and your engine idles, a spluttering sound with increasing vibrations are often viewed a sign of a faulty spark plug.

A Drop in Mileage

Another common sign of a worn out spark plug is low mileage. If the fuel you use is consistent but you still experience low mileage, it could be a sign of failed spark plugs. A reduced mileage can be a sign of a blocked fuel filter or even a broken spark plug. It is imperative to use the right spark plugs for your car as recommended by the manufacturer for optimal performance and mileage.

Poor Acceleration

When your car has poor acceleration, it could be a hint to have your spark plugs checked and replaced. Poor acceleration may include delayed reaction or even lack of response when revving your gas pedal. I such a scenario, pushing the gas pedal down do not cause any immediate boost in the speed of the car. This may cause the engine to appear being overworked.

Engine Misfires

Worn out spark plugs can also cause engine misfires. However, modern cars can have the same problem due to a sensor malfunction. In the case of worn out spark plugs, the problem could result when the wire of the spark plug has been damaged. An Engine misfire results to intermittent sputtering or stumbling sound.

How long should you wait before replacing your Spark Plugs?

According to most auto manufacturers, Spark Plugs should be replaced once your car has a mileage of 30000 to 50000. Additionally, other factors such as the type of the spark plug and the condition of the car do impact the longevity of your car’s Spark Plugs. Spark Plugs made of copper have a short life compared to other common types of Spark Plugs made using durable material.

How can you test a worn out spark plug?

  • Firstly, remove the spark plug
  • Keep the spark plug in the spark plug cable
  • Place the spark plug on the frame
  • Ignite the car and observe for any sparks
  • You can also have your Spark Plugs checked by a certified mechanic

What should you expect when you replace your car’s Spark Plug?

Changing your car’s Spark Plugs after they’re worn out comes with numerous benefits. A new Spark Plug ensures your car Ignites without any hesitation giving you the confidence to enjoy your ride. New Spark Plugs:

Improve the Fuel efficiency – according to data from National Institute for Automotive Service Excellence, misfiring sparks reduces efficiency of fuel by about 30%. When new spark plugs are replaced, fuel efficiency is maximized thereby saving on cost.

Reduce emission by your car- the Environmental Protection Agency reported that regular turn ups of engine save gas while at the same time reducing harmful gas emission.

Easy start of your car- igniting your car with new Spark Plugs often feels like revving a new engine. If the installation is successful, performance and ignition problems will be a history.

Check out this You Tube video

that will give you a more comprehensive and easy to understand concepts on how to replace your car’s Spark Plugs when they’re worn out. I would love to hear from you so feel free to comment or ask any questions on Spark Plugs.

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