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Without a working spark plug, your vehicle wouldn’t be able to run at all. What are the benefits of changing spark plugs?

Spark plugs are very small and forgettable, but have a very important role to play in your vehicle’s functionality. If your spark plug stops working or has any kind of problem your car will not run as smoothly.

Some of the benefits of changing spark plugs include a more efficient and smoother engine. It also provides improved acceleration and horsepower and allows for better fuel economy. Spark plug replacements will also result in lower carbon emissions.

Over time and use, spark plugs go through plenty of wear and tear, just like any other part of your vehicle. This will affect their performance and thus the performance of your car.

In our research, we tried and tested vehicles with new spark plugs to see how they compared in performance with vehicles with older spark plugs.

Table of Contents

Benefits of Changing Spark Plugs

Spark plugs are what creates that initial electric spark to make the engine ignite. Without it, your vehicle doesn’t work at all. That is why it is important to make sure the spark plug in your vehicle is functioning properly and replace it when the need arises.

Let’s consider some of the benefits of changing the spark plug.

Improved Efficiency and Performance of Engine

When your spark plug gets too worn out, it can cause the engine to misfire. This is when one or more of the cylinders in the engine doesn’t produce power. It can also cause other engine problems like bucking, stalling or slow starts. It can also make the engine run roughly.

Worn out spark plugs also tend to have a wider gap than new ones. This results in the consistent combustion system getting interrupted, which results in poor acceleration, misfires and rough idling.

Older spark plugs will also have efficiency problems around ignition because they will take up a higher ignition voltage.

With a new spark plug, all of these issues go away, so you can improve your startup performance and the engine as well.

Reduced Cold Starts

One major advantage of getting an old spark plug replaced is the reduced number of cold starts. Cold starts are when you try to start the engine while its temperature is much lower than its usual operating temperature. This usually happens because of cold weather.

Because car batteries will produce a lower electric current when temperatures are lower, the spark plug needs to have the capacity to generate a strong enough spark to make the engine ignite. Older and worn-out spark plugs need a higher voltage to do so, and by replacing them, you can reduce the number of cold starts your engine produces.

Improved Combustion Engine Functioning

The spark plug is in charge of burning the air-fuel mixture in the combustion chamber. When your spark plug becomes old and worn out, it takes up more power to keep the engine running and can cause trouble with the gas mileage of the vehicle.

In the long run, this can result in greater damage to the vehicle itself. By regularly replacing the spark plug, you can avoid such damages and keep the engine in good shape.

Improved Fuel Efficiency and Economy

Research by TheNational Institute of Automotive Service Excellence (ASE) found that the misfires caused by old and faulty spark plugs can actually reduce the fuel economy of your car by about 30%. Regardless of how much fuel your car is designed to consume, misfires can cause fuel economy problems in your vehicle.

This means that your engine churns more fuel to try and generate a spark that is powerful enough to combust the air-fuel mix to ignite the engine. As such, your maintenance costs and fuel refill costs also shoot up.

By replacing your spark plug in time, you can avoid these issues and revert your car’s fuel economy, efficiency and gas mileage back to its optimal conditions.

Lower Carbon Emissions

On top of just causing damage to the vehicle itself, older and faulty spark plugs can also cause damage to the environment. Because older spark plugs put pressure on the engine, it releases many harmful emissions while trying to function normally. On the other hand, if you replace the spark plug in time, you can reduce the harmful emissions since the plugs would be operating at their optimum power.

The Environmental Protection Agency (EPA) also says that maintaining your car regularly and timely replacement of older spark plugs can greatly reduce the number of harmful emissions your vehicle releases into the environment.

Improved Horsepower and Acceleration

A new spark plug will also have a significant impact on the car’s horsepower.

Spark plugs will not actually increase the car’s horsepower, but they do bring the car’s system to its optimal combustion state and thus improve the current flowing through the wires in the system.

This results in the vehicle running with the best acceleration control, and a much faster engine response while you’re driving.

How Often Should You Change Your Spark Plugs?

Knowing that you should change the spark plug on your vehicle isn’t enough; you also need to know when to do it. This would depend on how much you drive, how often and the kind of spark plug you have in your vehicle.

A conventional spark plug has a lifespan of about 30-50,000 miles with some going up to 60,000 miles as well. After your vehicle has driven this much, you will have to change the plug.

There are also long-life spark plugs, which can last up to 100,000 miles.

Spark plug replacement shouldn’t necessarily wait until something goes wrong – you can change them as a preventative measure to avoid any of the problems of a faulty spark plug. After all, you don’t want to wait till your engine has already started causing you trouble before you do something about it.

A key point here is to perform spark plug check ups regularly. All plugs will wear out over time, so you can keep an eye out on them.

If you know your mileage history, you can make a pretty good guess around when to change your plugs, but there are also some signs that your spark plug may need replacing. Poor acceleration, engine noises, rough idling etc. are some of these signs. If you encounter any of them, you may want to get your spark plugs checked out by a mechanic, and replaced if necessary.

Should You Replace All Your Spark Plugs At The Same Time?

Most commonly, spark plugs are replaced as a set. This is because for optimal combustion, they all should be performing at a similar level. If one plug is working at optimal levels while others are faulty, your engine can fall out of sync and possibly get damaged.

Changing a single plug is also inconvenient in that you’d have to get them checked out much more frequently than if you were replacing them all at once. By changing one at a time, you’d have to keep your eyes on all the rest to know when each of those needs replacing.

Additionally, all spark plugs in a system need to have the same electrical resistance. If one is better than the other, again, the engine falls out of sync. This results in the combustion system – which usually stays consistent –in being pressured and causes more wear and tear.

Replacing your spark plugs is standard practice, and while they don’t have to be replaced together, it is in your own – and your vehicle’s – best interest that you do so in a set.

Changing your vehicle’s spark plugs can have a number of benefits, with the main one being the improved engine performance and efficiency. This efficiency also results in decreased cost of fuel and maintenance and keeps your vehicle running smoothly for a much longer time.

Benefits of Changing Spark Plugs

About The Author

Charles Redding

Charles Redding

I've spent many years selling cars, working with auto detailers, mechanics, dealership service teams, quoting and researching car insurance, modding my own cars, and much more.

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