The Best Spark Plugs for Your Car – A Complete Guide!

A spark plug is a small, relatively cheap part of your car – but it is a vital part of the system. Without a spark plug, your car won’t be able to start at all. With a bad spark plug, or a very old, worn spark plug, your car’s performance could drastically drop – it can impact everything from start-up to power, fuel economy, and could even cause strange rattling and knocking sounds.

In our guide to finding the best spark plugs for your car, you’ll find out more about how spark plugs work, and about the different types, you can buy (and their pros and cons). We’ll also recommend some of the best spark plugs out there and show you what to look out for when you’re shopping for a new one.

Without further ado, let’s take a look at what a spark plug is, and how it works.

Denso #3417 Iridium Long Life Spark Plugs SK16HR11 | Amazon

Iridium spark plugs are considered the best type of spark plugs, and the Denso #3417 Iridium Long Life Spark Plugs is our top recommendation! It lasts a really long time and prevents poor fuel economy.

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Table of Contents

Summary: Top Recommendations

  1. ACCEL 0736 Copper Core: Best Copper Spark Plug
  2. NGK G-Power Platinum Spark Plug: Best Single Platinum Spark Plug
  3. Autolite Double Platinum Spark Plug: Best Double Platinum Spark Plug 
  4. DENSO Iridium Long Life Spark Plug: Best Iridium Spark Plug  

How do Spark Plugs Work?

Spark Plug

You’ve probably heard of a spark plug, but do you know how it works?

Spark plugs give a tiny spark of electricity – the spark that will allow your car to start. The electricity crosses a tiny gap, which starts the ignition for the combustion that your car needs to start up. As soon as the engine’s pistons start moving, your car begins to power up. So, without a spark plug, your car isn’t going anywhere.

All of this happens in a few milliseconds – the piston that draws fuel and air in the cylinder will be at TDC (Top Dead Center) when the plug shoots out the small bolt of electricity. Everything about this process is timed to perfection.

The second function of the spark plug is to transfer heat away from the combustion chamber, another very important job. ‘Thermal performance’ is the phrase used to describe how well the spark plug dissipates heat, and how well it holds the right temperature.

Most vehicles usually have one spark plug per cylinder – and most cars on the road will have four cylinders. Diesel cars do not have spark plugs – they work slightly differently, using something known as a ‘glow plug’ instead.

Spark plugs are small and inexpensive and are made from different types of materials – which one is suitable for your vehicle will depend on a few different factors (which we will discuss later in this article).

Spark Plug Parts

Spark plugs are made up of the following:

  • Insulator – this has good thermal conductivity
  • Center – Electrode – again, this must-have good conductivity
  • Terminal Stud – made from mild steel
  • Shell – made from machined mild steel
  • Ground Wire – usually made from the same material as the center spark plug wire
  • Washers – usually made from copper or steel

Hot Plugs and Cold Plugs – What’s the Difference?

car plugs

You can either get hot plugs or cold plugs. A hotplug is the most commonly found. It has more insulation than a cold plug and is kept at a higher temperature. This helps to burn off carbon deposits more efficiently. They tend to last longer.

Cold spark plugs are, as the name may suggest, a little cooler. Heat can be transferred out of the engine via the combustion chamber. If a car has a high horsepower, it’s more likely to have a cold spark plug.

Heat Range

Spark plugs vary in the amount of heat they dissipate. The heat rating of spark plugs is indicated by a number. Lower numbers mean a hotter type of spark plug, whereas a high number indicate a colder type. If you’re looking at spark plugs, make sure you check the number to see what type you’re getting.

Thread Size

Spark plugs come in varying thread sizes – again, you’ll need to make sure you get the right size for your vehicle. You will see the thread size denoted by letters:

  • 8mm – I,Y
  • 10mm – U
  • 12mm – X,XU
  • 14mm – J, P, PQ, Q, QJ, K, KJ, PK, PT, S, SF, SK, SVK, T, W, TR
  • 18mm – L, M, MA


Gapping refers to the process of making sure that the gap that the spark of electricity has to jump across is exactly the right measurement. If it’s not right, the engine may fail to start-up properly.

Sometimes, spark plugs come ‘pre-gapped’, but it can be a good idea to check the gap yourself. You can use a feeler gauge or other measuring tools to do this. It can be a fiddly job, but it’s definitely worth doing if you think your spark plug isn’t working efficiently.

Ignition Wires

Spark plug wires transfer the spark from the coil to the plugs. The action of this, repeated over time, can cause the plug wire to become brittle, or to break completely.

When you check your spark plugs or replace them, it’s always a good idea to check the wires, too. They may need to be replaced along with the spark plug.

Identifying a Bad Spark Plug

How can you tell if your spark plug needs changing?  Well, a bad spark plug can cause a number of issues:

  • A spark plug that completely fails will stop your car from starting
  • Your car won’t be able to sustain maximum power
  • Your vehicle may see a drop in fuel economy, with fuel being wasted
  • You may be able to start the car, but it might feel jerky when it starts
  • It could make a rattling or knocking sound – that is the pistons making a strange noise when the combustion fails

Ideally, a spark plug needs to be changed after 30,000 miles (it’s always a good idea to keep a record of when you last changed your spark plugs for this reason). Not all spark plugs are created equally – some are stronger than others, and wear and tear will start to cause issues after a while. A deposit can form on spark plugs from the air-fuel mixture (this can cause that ‘jerky’ feeling when you start-up your car). The gap that the spark has to jump can also widen over time, which means combustion might not always take place.

A new spark plug will help your car to start smoothly every time. It will help your car to perform properly, save you from fuel loss, and help reduce harmful emissions.

Here’s a quick rundown of what your spark plug may look like if it is damaged, and what may have caused it:

  • Carbon Fouled – a carbon-fouled spark plug will have soot on the electrodes and the insulator tip. This could be caused by driving at low speeds, rich fuel, or a dirty air filter.
  • Oil Deposits – black oil deposits could suggest that oil is leaking into the cylinders – it’s really important to get this checked over by a mechanic.
  • Burned – if your spark plug looks burnt, or partially melted, it suggests that the spark plug is running too hot. The engine could be overheating, or the spark plug could be too loose.
  • Wet – sometimes, if you try to start up the engine without it firing up, you can cause your engine to flood. In this case, the spark plug may be wet, and you’ll have to wait for it to dry.
  • Broken Electrodes – if the electrodes are broken, it’s probably the wrong spark plug for your vehicle. It’s really important that you choose the right spark plug for your vehicle – check with your manufacturer to see if you have the right spark plug or not.
  • Worn Electrodes – eventually, your spark plug will start to wear out. A classic sign of this is if the electrodes start to wear down. If you see this, it’s time to buy a new one.
  • Misfires – If your car backfires or hesitates when you step on the gas, you might have faulty spark plugs. You may also experience violent jerking motions or very slow acceleration when you press the accelerator, indicating your spark plugs aren’t working like they should.
  • Rough Idling – If your engine runs rough while it’s idling, but seems to run fine when you press the accelerator, this could indicate that you need new spark plugs. Be aware of how your car runs while you’re driving and while you’re sitting at stoplights.
  • Charred Wires – If your current spark plug wires are charred on the ends, you need to replace the wires and the spark plugs. Your spark plugs are beginning to show signs of melting, which doesn’t happen when spark plugs are functioning properly.
  • Changes in Fuel Consumption – Changes in fuel consumption can mean a lot of things. Your spark plugs aren’t always the culprit, but if you begin to notice significantly reduced fuel economy, the spark plugs are a good place to start.
  • Trouble Starting – If you’re having trouble starting your engine altogether, you may need new spark plugs. It could also be a variety of other things like a dead battery, a bad alternator, or a faulty starter, but those are all the places you’ll want to start.

Keeping an eye on your spark plugs is a great way to properly maintain your car.

Repairing Spark Plugs

bad spark plugs

Sometimes, you can help your spark plug to last a little longer. It could buy you several thousand more miles, which isn’t too bad at all for a bit of work.

A build-up of soot on the spark plug is fairly easy to clean up. You can check the manufacturer’s instructions to see how to do this safely. You can use a piece of very fine sandpaper to gently sand it, clearing out debris that may have settled in the grooves. You can blow out the debris using a blast of air. You can also get a spray-on plug cleaner.

While you’re doing this, you can check the spark plug for any cracks of problems, and then you can set the gap to the correct width (again, check the owner’s manual for information about this).

Changing Spark Plugs

How do you install a new spark plug? Your new spark plug should come with instructions, but the process looks a little like this:

  • Clean out the spark plug hole in preparation for the new spark plug
  • Give the threads of the spark plug a light coating with a little oil from the oil dipstick (be careful to avoid getting oil on the electrodes)
  • Thread the plug into the engine by hand, turning it clockwise (‘seating the plug’). Consider using a spark plug starter – this helps you to grip onto it properly
  • Engage the plug by hand, turning it at least two times before using the spark plug socket and ratchet
  • Slip the spark plug socket over the spark plug, attach it by the ratchet handle, and keep turning it. Don’t overtighten it – but make sure it’s in pretty tight.
  • Check the cable – if it is frayed or cracked, you’ll need to replace it. Apply a little silicone lubricant to the inside of the boot, and then push it over the terminal of the new plug, and press into place.

There are plenty of videos online which will give you much more of a visual idea about how this works – if you feel confident and you want to give it a go, it could save you a little money. If you’re unsure, it’s usually better to take it to a professional.

How the Manufacturer Decides Which Spark Plugs to Use

The manufacturer of your vehicle put some time into deciding what type of spark plugs to use. They design their vehicles in a certain way and take into account what kind of efficiency the spark plug will provide on a particular engine configuration.

The owner’s manual will recommend the type of spark plug the manufacturer used, and there’s typically a reason for it. It’s all based on the model of your car and how it was marketed.

For instance, sports cars designed as performance vehicles will typically take cold spark plugs while older vehicles generally perform better with copper spark plugs because they were designed when copper spark plugs were popular.

What to Look for When Buying a New Spark Plug


There are a few things you’ll need to keep in mind when buying a spark plug:

  • Vehicle compatibility – the first thing you’ll need to do is to check which spark plug is compatible with your car. If you’re buying a spark plug on Amazon, you will be able to input your car’s model and year of manufacture to check whether it is compatible or not. If you’re buying it from a store, the staff may be able to advise you.
  • Manufacturer’s instructions – Sometimes the manufacturer’s instructions for your car will advise you on which model of spark plug they recommend, which takes the guesswork out of it for you. They will also tell you which kind of spark plug you should buy – it’s best to stick to that, if possible, and not downgrade to a cheaper variety.
  • Price point – The price point isn’t as much of an issue with spark plugs as it will be for other vehicle parts, because they’re pretty low in price anyway. However, the price of, say, an iridium plug may put you off upgrading.
  • Wear – How long will your spark plug last? Although they cost a little more, tougher materials tend to last longer, meaning you’ll be able to go longer without having to replace it.
  • Age of Vehicle – some vehicles – like pre-1980’s vehicles – are more likely to use copper spark plugs. You may not be able to use spark plugs made from tougher materials on these types of cars. Again, the owner’s guide to your vehicle should be able to give you this information.

Spark Plugs and Emissions

Before we continue, a quick note on spark plugs and how they impact emissions. Vehicle manufacturers are being called to do their best to reduce emissions. This is vitally important work and must be taken seriously.

However, sometimes we can do our part to reduce emissions from our vehicles, too. Small steps, like changing your oil, using premium gasoline, and checking for leaks can really help your car to run efficiently.

Worn spark plugs and spark plug wires can impact your emissions, and they would give you a worse score on an emissions test. A bad spark plug can increase your hydrocarbon and carbon monoxide emissions. To help offset this, you can buy a good-quality spark plug and make sure they’re properly gapped – this will help your car to run more smoothly.

The Best Spark Plug for Your Vehicle

It’s always best to check your owners manual for the recommended spark plugs. However, if you’ve done any performance modifications or you want a longer life out of your new spark plugs, you may want an upgrade.

The easiest answer is always to stick with what the manufacturer recommends, because they designed the car and know what it needs. Their recommendation is going to be the best one for most people.

But chances are, if you’re reading this article, you’re not most people. So here are some things to think about.

Extended Life Spark Plugs

One thing to consider when getting extended life spark plugs is the idea that they cost a lot more money, but you won’t have to replace them again in the next ten years. If your engine configuration makes it difficult to access the spark plugs at the back, you may only want to mess with it once every ten years.

Spark Plugs for Better Performance

If you’re looking for better performance out of your vehicle based on your new supercharger, you’ll want to look into spark plugs that run colder. Even if you just want better gas mileage, think about springing for iridium spark plugs.

Sticking to Manufacturer Recommendations

Even if pursuing an upgrade to your spark plugs, the easiest way to transition is to use the same brand the manufacturer recommends, even if you switch materials. That way you reduce the risk of issues when it comes to installation and efficiency.

Upgrading your spark plugs depends on your driving profile and your engine design. Always remember that without great vehicle maintenance, your spark plugs won’t do you any good no matter which ones you choose.

spark plug mercedes

When it comes to spark plugs, you’ll see the same brands popping up again and again. Here’s a little more information about the biggest brands:


Of course, Bosch is a household name. A German multinational engineering and technology company, they have their headquarters near Stuttgart in Germany and were founded in 1886. They’ve been making spark plugs for a whopping 111 years – and they now produce a huge amount of spark plugs for vehicle manufacturers – including cars, boat engines, jet skis, garden equipment, water pumps, and more.


NGK Spark Plug Co., Ltd, was founded in 1936 and is based in Nagoya, Japan. They sell spark plugs and related products for internal combustion engines.


DENSO Corporation is an automotive components manufacturer. They’re based in Kariya, Aichi Prefecture, Japan. They became independent from Toyota Motors in 1949, but around a quarter of the company is owned by Toyota.


Autolite (or Auto-Lite) is based in the US, and they create spark plugs and ignition spark plug wire sets. The company can be traced back to 1911.

Copper Spark Plugs

copper plug

Made with a solid copper core, the center electrode is made from nickel alloy. The alloy is 2.5mm in diameter – which means it requires a higher voltage, as the spark has a bigger gap to jump. Nickel alloy is a little softer than other materials, which means it will wear out more quickly. They’re normally found in older vehicles, which are more likely to have low voltage distributor-based ignition systems.

Copper spark plugs require more frequent changing – every 20,000 miles. They have the advantage o being cheap, which is great.

Pros of Copper Spark Plugs:

  • Great for older vehicles
  • Cheaper price point

Cons of Copper Spark Plugs:

  • Can’t be used with newer vehicles
  • Need to be replaced more often

Best Copper Spark Plug – ACCEL 0736 Copper Core 

ACCEL 0736 Copper Core (4 -pack)

This is a great spark plug if you want a more efficient burn of air/fuel. It also has less fouling misfire and flame dissipation. It has an instant throttle response and better fuel economy than other copper core spark plug. It has 14mm threads which help to protect your cylinder heads.

They’re also, like other copper-core spark plugs, very reasonably priced – these come at under $20 for a pack of four, which is great.

Accel 0736-4 Copper Core Spark Plug | Amazon

Looking for copper spark plugs for your car? You can't go wrong with the Accel 0736-4 Copper Core Spark Plug!

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02/18/2024 09:00 pm GMT

Other Copper Spark Plugs

Champion RE14MCC4 (570) Copper Plus

Don’t write copper spark plugs off because they’re cheap. We already know that some cars are designed specifically for copper spark plugs, and you can’t upgrade. There are good reasons for that.

This copper spark plug is one of the best. It’s not innovative or fancy, but it gets the job done with extreme reliability. It has built-in anti-corrosion resistance, so it’s dependable and affordable.

Champion RE14MCC4 (570) Copper Plus Replacement Spark Plug | Advance Auto Parts

This Champion spark plug features a copper core electrode that provides increased conductivity and heat control for good overall wear.

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NGK 6240 Copper Spark Plug

This copper spark plug features quality and reliability. NGK is the leading manufacturer of spark plugs that help improve gas mileage, so if you’re looking for better fuel economy, this is an excellent choice.

The fuel ignition and throttle response are excellent and it features better heat transfer thanks to the alumina silicate ceramic insulator and laser-welded electrode tip. It’s also corrosion-resistant.

NGK 6240 Spark Plug | Amazon

Trivalent Metal Plating Provides Superior Anti-Corrosion and Anti-Seizing Properties.

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02/20/2024 10:46 pm GMT

Platinum Spark Plugs

The primary benefit to platinum spark plugs is that they will last for up to 60,000 miles. However, they’re also more expensive. Some drivers swear by these types of spark plugs, saying their car performs better in both highway traffic and city traffic. They also attest to getting better cold starting.

Single Platinum Spark Plugs

Single platinum plug is similar to copper plugs, but with platinum, disc welded to the tip of the center electrode. It’s tougher than nickel alloy, lasting for up to 100,000 miles. It’s also great for preventing deposit build-up because it runs at higher temperatures than a copper core spark plug. They’re usually seen in newer vehicles, with DIS (distributor-based ignition systems).

They do tend to be more expensive, as platinum is a much rarer material than copper. They do, however, offer excellent longevity, and the gap will not widen as the metal wears away. This should eliminate the problem of not being able to start your car reliably.

Some single platinum plugs may have a fine plug wire’ center core, which has one or more platinum discs in it. It means that it’s thinner in design.

If your car’s instruction manual says to use platinum spark plugs, do not be tempted to substitute for a copper version – make sure you stick with platinum.

Pros of Single Platinum Spark Plugs

  • Still relatively cheap compared to other types
  • Excellent longevity – up to 100,000 miles
  • Gap won’t widen as the metal wears away

Cons of Single Platinum Spark Plugs

  • Can’t be used in older vehicles

Best Single Platinum Spark Plug – NGK G-Power Platinum Spark Plug

NGK G-Power Platinum Spark Plug (6-Pack)

NGK is a great brand when it comes to spark plugs, and this model is no exception. At an excellently low price point, this comes in at under $25 for six spark plugs – so it should keep you going for a while. They’re reliable, easy to install and come pre-gapped, taking a lot of the work out of installation for you.

NGK 7090 BKR5EGP G-Power Spark Plug | Advance Auto Parts

Special configurations are used for the insulator noses to improve throttle response and prevent fouling with corrugated ribs on insulator to prevent flashover.

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Double Platinum Spark Plugs

Double platinum spark plugs differ from single platinum versions in that they have platinum plating on the center electrode and the ground electrode. This prevents the side-to-center spark from being ‘wasted’ – essentially making them work very well. The plates stay sharp for a long time, which make them last longer.

Again, it’s best to stick with the type of recommended spark plug by your manufacturer. You cannot downgrade to a single platinum spark plug or a copper spark plug.

They do, however, have a higher price point (as it uses twice the amount of platinum as a single-platinum spark plug).

Pros of Double Platinum Spark Plugs

  • Lasts a very long time
  • Works really well

Cons of Double Platinum Spark Plug

  • More expensive than single-platinum and copper spark plugs

Best Double Platinum Spark Plug – Autolite Double Platinum Spark Plug

autolite app104 double platinum spark plug

The Autolite Double Platinum spark plug promises virtually no gap erosion – helping to avoid unreliable start-ups.  It can give improved fuel economy and quick-firing action due to the necked-down center electrode. The high-nickel alloy side electrode maintains a precise gap, and the full copper core electrode is reliable. It has great reviews, too.

Autolite APP5683-4PK Double Platinum Spark Plug | Advance Auto Parts

Autolite® Double Platinum Spark Plugs are a premium plug providing superior performance and platinum-to-platinum firing for a longer lasting spark plug. Autolite® Double Platinum Spark Plugs are engineered to provide easier starts, quicker acceleration and improved fuel efficiency.

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Other Platinum Spark Plugs

Bosch (4501) FGR8DQI Platinum IR Fusion Spark Plug

Bosch hits the mark again with some platinum spark plugs this time. This Bosch Spark Plug is actually a platinum/iridium combination spark plug that comes with increased performance, easy installation, and long life.

The unique ground electrode design changes the cylinder tip for a different design than what’s on other similar spark plugs of the same quality. This advanced technology offers smoother operation.

While they’re easy to install, you do need to follow the instructions very closely to ensure you do it correctly. You may experience problems with durability if you don’t get install this Bosch Spark Plug the way the Bosch website indicates.

Denso (4504) PK20TT Platinum TT Spark Plug

Despite the fact that they’re not well-known, Denso has another spark plug on my list. This time we’re looking at a platinum, twin-tipped spark plug. The dual platinum construction Denso Spark Plug features durability in a platinum disc and a platinum electrode tip.

The tip on this Denso Spark Plug is 11mm in diameter, which is quite large, but under normal driving conditions, you’ll hardly notice this affecting your performance. The Purified Alumina Powder used for insulation lengthens the lifespan and increases thermal conductivity.

This is a fantastic spark plug at its price point. It’s not iridium, but it still features longevity and durability you can count on in your everyday driver.

Denso (4504) PK20TT Spark Plugs, Pack of 4 |

Give your ignition system a jolt with a Denso Spark Plug. These top-notch replacement plugs are suitable for use in just about any vehicle and maintain a stable operating temp under all engine loads. Choose from a wide-range of electrodes and designs for your specific vehicle. 12-month warranty.

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Iridium Spark Plugs

Iridium Spark Plugs

Considered to be the best type of spark plug, they have a great amount of power and more complete combustion, which will help your engine to run much more smoothly. Due to the toughness of iridium, these spark plugs have a very good lifespan – sometimes up to 25% longer than platinum spark plugs. They usually have ‘fine-wire’ centers to easily conduct electrical energy.

COP ignition systems will usually require iridium spark plugs, or an iridium/platinum combination spark plug. Sometimes, manufacturers cut a ‘U’ or ‘V’ shaped-channel into the ‘spark receiving’ side of the electrode. This prevents quenching of the flame, allowing it to grow more quickly – enabling your car to start-up very smoothly and quickly.

Pros of Iridium Spark Plugs

  • Considered to be the best
  • Very good lifespan – lasts even longer than double platinum spark plugs

Cons of Iridium Spark Plugs

  • The price jump is pretty big
  • Will not work on older vehicles

Best Iridium Spark Plug – DENSO Iridium Long Life Spark Plug

denso iridium spark plugs

This was the first automotive plug to utilize iridium – so it made a big difference to the future of spark plugs. It prevents slow acceleration, poor fuel economy, and engine misfires – and it lasts a really long time. It comes pre-gapped, and reviewers note how long they last without needing to be replaced – which may make up for the higher price.

Denso #3417 Iridium Long Life Spark Plugs SK16HR11 | Amazon

Iridium spark plugs are considered the best type of spark plugs, and the Denso #3417 Iridium Long Life Spark Plugs is our top recommendation! It lasts a really long time and prevents poor fuel economy.

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Other Iridium Spark Plugs

Denso (3297) SK20R11 Iridium Spark Plug

This isn’t the most well-known brand in auto parts, but it makes the list for good reason. They make great replacement parts of excellent quality, especially at this price point. These spark plugs will thread easily into your cylinders without binding.

They provide a reliable spark for smooth engine performance. They will help improve gas mileage, making them a great option at an affordable cost, particularly in the lineup of iridium spark plug options.

The only potential drawback is that Denso doesn’t make them for all North American cars, so you may not be able to find this particular spark plug for your domestic model.

Denso # 3297 Iridium Long Life Spark Plugs | Advance Auto Parts

Patented U-groove ground electrode design fires leaner mixtures than conventional plugs.

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Bosch 9617 Double Iridium Spark Plug

Bosch is well-known for producing a lot of quality technology in home appliances. Their competence in component production translates well to auto parts and these spark plugs will improve performance and offer almost four times the service life.

They feature extra durability, thanks to the double iridium inlay. The laser welding results in better retention. They’re also corrosion-resistant, which increases both performance and durability. They’re also easy to install.

As you can imagine, these are pretty pricey. As with most of Bosch’s excellent products, they are top-of-the-line, and the price reflects that. You really can’t expect this kind of quality without spending the extra money.

Bosch 9617 Double Iridium Spark Plug | Advance Auto Parts

The ultra fine wire design and laser welded, tapered ground electrode deliver the ultimate in ignitability and high performance.

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Quick Tips for Buying the Perfect Spark Plugs

Armed with all of this information, what do you really need to know? Here are four quick things that should be pretty easy to remember.

Bring your vehicle information

You need to know information about your vehicle in order to choose the right spark plugs. You’ll need to know:

  • Year
  • Make
  • Model
  • Engine size
  • Carburetor or fuel injection type
  • Number of cylinders

You can get this information in the owner’s manual or your vehicle registration. If you can’t remember it, take it with you when shopping. It’s also a good idea to check your owner’s manual for the type of spark plugs they recommend.

Don’t downgrade

You don’t have to stick with the manufacturer’s recommended spark plug, but never downgrade. Don’t cut corners or try to save money. You could suffer a decrease in performance, or worse. You could damage your engine.

However, as long as your engine is not designed for a specific type of spark plug, you can always upgrade.

Spend money to save money

Spending a little bit more money on quality spark plugs will actually save you money in the long run. You’ll get better performance, better quality, and a longer life out of them. You’ll also enjoy better gas mileage, which means you’ll save money on gas, too.

Not to mention, you’ll save money on engine repairs because you won’t be doing damage to your engine.

Consider vehicle use

The last thing you need to consider is how you use your vehicle. If this is your everyday driver, the manufacturer’s recommended spark plugs will work just fine for you. You can upgrade if you’d like to see some of those money-saving benefits over the long term.

However, if you drive a performance vehicle or a special purpose vehicle, consider an upgrade that benefits your car’s performance so you can take it out and drive it fast on the weekend.

How to Replace Spark Plugs

If you’re considering replacing your spark plugs yourself, you’ll want to make sure you do your research. You can consult your owner’s manual or look up your make and model on YouTube for a more comprehensive guide tailored to your vehicle, just make sure you’re looking at a reputable source.

However, here’s a really great comprehensive video on how to inspect spark plugs, figure out which spark plugs are best for your car, gap spark plugs, and replace spark plugs and wires.


FAQ’s About Spark Plugs

Do sparkplugs always need to be gapped?

The gap between the center and the side electrodes must be at the right distance (exactly), otherwise, the spark plug will not fire efficiently. If you need to ‘gap’ your spark plug yourself, you’ll need a feeler gauge. Many spark plugs come pre-gapped, but it’s usually a good idea to make sure it’s the right gap anyway.

Do spark plugs increase performance?

Yes. Changing a spark plug over will help your vehicle to work more efficiently, reducing exhaust emissions. Newer spark plugs also require less voltage in the ignition system.

Are spark plugs powered by the battery?

Yes – electrical current travels from the battery to the induction coil, which raises the voltage to ignite the plugs.

Will a failing spark plug cause the check engine light to come on?

Yes – worn spark plugs or spark plug wires can cause the check engine light to come on.

What tools do I need to change a spark plug?

You’ll need a ratchet, a gap gauge, and a torque wrench. You might also consider a spark plug socket.

Are all spark plugs the same size?

No. There is one size that is particularly common, but there are varying sizes. You’ll have to check the manufacturer’s instructions to see what size your car needs.

How often should I change my spark plugs and wires?

This isn’t the easiest question to answer because it depends on a lot of factors. High-quality spark plugs last longer than low-quality spark plugs. You should always replace your wires at the same time you replace your spark plugs.

It’s recommended that you change your copper plugs every 10,000-25,000 miles, your platinum plug every 60,000 miles, and your iridium plug every 100,000 miles. However, if your spark plugs go bad before that, you’ll have to do it sooner.

What causes spark plug failure?

Carbon buildup on the center or ground electrode is the most common cause of spark plug failure. This carbon buildup fouls the plug and causes it to misfire or cease firing at all. Using quality fuel and properly setting spark plug gaps will prevent this issue.

How do spark plugs age?

Spark plugs are installed in an area of your engine that gets very hot, so they have to be extremely durable and able to withstand a lot of heat for long periods of time. The ceramic material in your spark plugs can crack or break in these extreme conditions over time.

As the electric current passes through the electrode over and over again, it causes wear and tear, corrosion, and carbon buildup. All of these conditions take a toll on your spark plug and its life.

Why should I replace my spark plugs?

When your spark plugs start to go bad, your engine will lose performance or stop working. It can cause misfires, violent jerking when you press the accelerator, and many other less-than-desirable actions. Replacing your spark plugs when they go bad comes with many benefits.

Your engine will run smoother and you’ll have much better driving experience. It’ll be more comfortable to ride in your car and you may notice that driving is less frustrating. Your gas mileage may improve, saving you money on fuel. Because properly working spark plugs reduce the strain on your engine where the combustion process is concerned, it will use less fuel to get moving.

Making sure your spark plugs work will ensure that your engine and your vehicle continue to run as they should without extra damage. The violent jerking that happens as your spark plugs go bad can cause wear and tear on many other parts of your car.


We hope that this article has helped you to understand what spark plugs are, how they work, and the best type for your car. Spark plugs are absolutely vital – so it’s really important that you invest in one that is going to perform well.

Choosing a spark plug may sound as simple as replacing the one you currently have, but it’s always a good idea to understand how these things work, especially if you want to upgrade to a better-performing spark plug later down the line.

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