Car enthusiasts, old or young, probably got their hands dirty and fiddled around under the hood at least once in their lives. It is unavoidable; better yet, it is very enjoyable and part of the reason most of us start working on a DIY project waiting in the garage.
You know the drill: you dream about one of those cool and powerful cars you’ve seen in a magazine while you were a kid, or maybe you were inspired by one of the models your father owned and worked on every Saturday morning – whatever the make and model, it will haunt your dreams forever. Until you finally get one and it needs some TLC.
Having it parked inside your garage, waiting for you to work on it, even if it’s for 5 minutes at a time, is pure heaven. The second you turn that engine and it starts to purr like a kitten, the smile on your face says it all. Before you have a go at it, let’s just go through a very fast and summarized crash course on engine functionality, shall we?
Any internal combustion engine (whether it’s from your favorite car, truck or anything else) running on petrol or gasoline is based on a simple principle: small and controlled explosions are transformed into energy, driving components into a rotating force that turns the wheels – is that simple enough?
A carefully balanced mixture of gasoline and air is drawn in, compressed and ignited inside the cylinder chamber. The resulting explosion pushes the cylinders, which in turn put the car’s driveshaft the motion, which drives the gears and timing belt or chain, and so on.
The magic is a bit more complex than that, a story that passionate mechanics probably enjoy. But today we will stop there and go back a few steps and remember the part about controlled explosions.
Any explosion requires ignited fuel or, in this case, a carefully timed spark, and that’s where the spark plug comes in handy. This small and relatively unappreciated car component is responsible for triggering this explosion that puts everything in motion. A small electrical charge flows between its center electrode and ground electrode, creating a tiny spark.
Inexpensive and often overlooked, the spark plug is a vital engine component without which your car simply won’t move. No spark, no combustion — no running engine.
Spark Plugs: What To Consider
When you’re buying any parts for your car, especially for your engine, all components should be carefully selected. As such, we have decided to give you a few pointers that might help you before making your next purchase for brand new spark plugs. Here’s what you should consider when you’re replacing your spark plugs:
Material
The material used for the construction of the spark plugs is relevant to the engine’s purpose and specifications. Copper is ideal for older model vehicles, while platinum and iridium are best suited for modern engines. You could always choose platinum for an enjoyable mix between fuel economy, performance, and longevity, and go for iridium if you’re aiming for top speeds and performance.
Spark Plug Size
Another important factor to consider before making a choice is the size of the spark plugs. Take a closer look at the car’s owner’s manual and find out which size thread and nut you should be looking for.
Heat Range
Before feeling confused, let’s make one thing clear: a hot spark plug is considered to be a better heat insulator, while cold plugs were designed to conduct more heat out of the tip and lower its temperature.
Manufacturers have classified the heat range of a spark plug with a number, although you should be careful because some brands use an ascending scale for hotter plugs, while others have decided a descending scale might be a better idea for colder spark plugs.
Spark Gap
Spark plugs generate a spark with the aid of a gap, engineered to be adjusted using a gap tool. A single plug may be designed for several engine types, which means it may require some adjustments before fitting it to your engine.
Specialists use a gap gauge to measure the spark plug’s gap and ensure the spark is powerful enough to ensure the perfect combustion inside the cylinder room.
Pricing
- Lower than $3: Cheaper doesn’t necessarily mean worse. There are several affordable spark plugs considered to be very good, but you should carefully consider the aforementioned factors before going for the cheaper option.
- Between $3 and $9: Most spark plugs fall into this pricing segment and simply put, you just can’t go wrong with any of them, at least not for your average sedan or small city car.
- More than $10: These spark plugs promise a durable construction thanks to premium materials and advanced electrode designs. If it’s performance and efficiency you desire, expect to pay a bit more than on others.
As you start to understand what to look for, you should realize that spark plugs come in many different shapes, sizes and variations. Their physical dimensions are the first things to consider before changing your old ones, with characteristics and heat range not to be ignored either. Electrodes, the materials used for their construction and more are also important factors in choosing spark plugs.
Types of Spark Plugs
When it comes to spark plug types, these are the options:
- Copper – these are the basic and most affordable choices on the market. These spark plugs have recently been replaced by platinum and iridium spark plugs, with the latter offering improved performance, efficiency, and lifespan. Most modern engines simply cannot run copper spark plugs, but for those of you owning older vehicles or classic cars copper is still a good option.
- Platinum – Platinum plugs are the best choice for everyone: they deliver enhanced performance and improved fuel efficiency compared to copper plugs, while selling at a significantly smaller price than the the iridium ones. Furthermore, platinum spark plugs operate at a lower temperature, which means they will last about twice as long as their copper counterparts.
- Double Platinum – Double-platinum spark plugs sound as good as they perform. If you are looking for even more performance, efficiency and longevity, leave single-plated platinum plugs behind and go for this upgrade, that still costs less than iridium spark plugs.
- Iridium – The best spark plugs on the market, there is no doubt about that. These plugs were designed with the aid of innovative technologies for efficiency and performance. Ideal for high-performance cars, iridium spark plugs are what most of us would call pricy.
Failing Spark Plugs Signs
How do we spot a failing spark plug? There are a few signs hinting towards an aging spark plug so if you notice some of the following changes, it’s time for new ones:
- Rough Starts – if you have a tough time starting your engine, it might be because of worn-out spark plugs. Turning your ignition becomes pointless, although you hear the engine turning.
- Rough Idling – a smooth running engine is especially enjoyable to hear while idling at a red stop. However, extra-loud noises, rumbling or unusual vibrations might point towards old spark plugs.
- Misfires – an engine that seems to have a difficult time in keeping a pace and seems a bit choked or seems to run unevenly is an engine that requires new spark plugs.
- Slow Acceleration – delayed response times when hitting your gas pedal or slower acceleration is a common problem associated with old spark plugs.
- Increased fuel consumption – As spark plugs start to degrade, fuel efficiency will suffer, while the ECU attempts to compensate for the uneven explosion, with extra air and fuel allowed into the combustion.
Spark Plugs Inspection
If a spark plug’s electrode looks ok, everything is in working order. Removing spark plugs might not be as difficult as many believe, but you should have a clear idea of what a worn out or old spark plug looks like. Here is what you should consider:
- They Look Fine – If the plugs look ok and the engine works perfectly, there is no reason to invest money in new spark plugs.
- Looking Fine, but with red coating – If the engine is in fine working order, yet the plugs display a bit of a red coating, it just means that fuel additives from cheap gasoline have deposited on the spark plugs. Clean them off and put the plugs back in.
- Aging Look – Once the plug’s electrode looks worn, meaning it looks thin or brittle, it’s time for a replacement set.
How to Change Your Spark Plugs
As any other car component, even spark plugs wear down over time, which has some negative effects on your engine’s functionality: fuel economy, lowered performance and in some cases even internal damage.
To make sure all is well with your engine, changing your spark plugs should be a job best left for your favorite technician or mechanic – DIY car enthusiasts with some experience might want to change the spark plug themselves, but if this is your first time you should leave it to the professionals.
Before doing anything else, please consider consulting a service manual for your particular engine, where detailed explanations and steps to be followed will be indicated. Once again: follow the vehicle manufacturer’s recommendations regarding spark plugs.
New Spark Plugs Benefits
No one wants to be stranded in the middle of a road trip, right? Brand new spark plugs will give your engine a new life, preventing it from suffering any damage from misfiring. Here are a few benefits that come with a new set of plugs:
- Smooth engine, at idle or during long drives.
- Fast acceleration.
- Easy engine starts, even in freezing temperatures.
- Improved fuel economy.
The 20 Best Spark Plugs:
With all of that information in mind – you are welcome – let’s just spend some time focusing on the best choices on the market. One way or another, chances are you will be fitting one of these spark plugs to your engine at least once in your car’s lifetime.
NGK Iridium IX
As we have mentioned earlier, iridium-tipped spark plugs are the best choice you could make when buying a new set. NGK is a brand that’s always in the top three companies when it comes to spark plugs, and their Iridium IX product was designed to deliver the most performance out of your engine.
Enhanced throttle response and superior resistance is what NGK is promising, with these park plugs benefitting from a triple-layer gasket and anti-corrosion trivalent metal plating on the body and threads, which prevent seizing and allow for an easy change. These spark plugs will keep your engine running optimally for years to come.
Denso Platinum 4504 TT
If reasonable pricing and an all-around solid choice is what you are looking for, look no further than the Denso 4504 PK20TT Platinum spark plugs. With a noteworthy reputation on the market, this company has designed a set of spark plugs that has no significant impact on your budget.
Don’t let the affordable factor fool you, these platinum spark plugs will offer drivers an ideal blend between lifespan, performance and fuel efficiency. A platinum disc and platinum electrode tip will allow these spark plugs to ensure a smooth engine noise and functionality.
A feature worth mentioning is also the use of alumina powder, an insulator meant to increase thermal conductivity for a long time following first usage.
Bosch Copper with Nickel
Another major player on the automotive market, in general, and spark plug production specifically, BOSCH enters our list with yet another interesting option. This OE replacement plug promises a long lifespan and great performance, among many other things.
Low temperature conditions will no longer be an issue, with cold starts being a breeze thanks to its nickel chromium ground electrode. Aiming to offer optimum heat transfer, BOSCH fitted their spark plugs with an Yttrium-enhanced copper core center, making them great for heavy-duty usage as well.
The iridium firing pin was welded with a 360-degree continuous laser, the wire has been incredibly refined and the nickel-plated shell was meant to prevent seizing. Anti-corrosion and with no gapping required prior to fitting, these plugs are just what the doctor ordered.
NGK V-Power
NGK is one of the biggest names in the spark plugs world, which is why they deserve another entry on our list. Although not recommended for all applications, these spark plugs are ideal for you, especially if you’re a DIY enthusiast.
Designed to prevent corrosion and featuring anti-seizing properties, this spark plug was built with a unique cut, which aims at directing the spark to the edge of the electrode – this translates into an optimized explosion.
Available at an affordable price and suitable for various cars, trucks and even motorcycles, the V-Power plug features the brand’s proprietary Trivalent Metal Plating technology and promises anti-corrosion and anti-seizing characteristics.
With a 90-degree V-Power center copper or platinum electrode, and pure alumina silicate ceramic acting as an insulator, these spark plugs will deliver high performance, improved fuel economy and long-lasting usage.
ACDelco 17 Professional RAPIDFIRE
First things, first: these spark plugs are not iridium or fully platinum, which means they will not work in every vehicle out there. It might pay off for you to check your owner’s manual before opting out for ACDelco’s product.
Aside from that, Rapidfire plugs were designed for everyday use and they were meant to fit most engines. Completely manufactured from a copper core, these plugs promise incredible heat transfer and durability. Featuring a ribless insulator, these ACDelco spark plugs won’t have any problems with leakage.
Furthermore, the platinum on the center electrode ensures optimal performance and superior spark characteristics, while keeping voltage requirements at a minimum. There is nothing bad to be said about these plugs.
Champion Copper Plus
Champion Auto Parts is one of the oldest names in the spark-plug game and their products are among the most popular in the world. Their Champion Copper Plus C33-438 four-pack is a versatile and affordable option, totally worth considering before making a decision.
Owning an average vehicle or a classic car will allow you to get away with purchasing copper-based spark plugs. But these plugs might also fit small engines, such as the ones powering up lawnmowers, chainsaws and more. You should read your car’s manual or contact your vehicle’s manufacturer before attempting to install these spark plugs though.
It is true: a copper spark plug doesn’t last as long as other type of plugs on the market, but they’re simply the ideal choice for certain models. Designed to be impervious to rust, featuring a reliable copper core, and available at a $5 purchase price, these durable plugs seem the ideal choice if you are looking for maximum performance as well as a steady operating temperature, something of an issue with classic cars.
Autolite Copper
Speaking of classic car owners and copper-core plugs, if you’ve decided that only such choices will work for your particular car, don’t waste your time and money, check out Autolite’s excellent offerings.
Affordable, to say the least, Autolite’s copper spark plugs are sold in packs of four, with only $10 required for each set – if that’s not a bargain, we don’t know what is. These won’t get your car breaking any speed records, but they will handle their business very well.
Autolite delivers solid spark plugs, impressive thanks to their long-lasting construction and for their incredibly high rating according to customer reviews.
Champion Double Platinum
Going double platinum, whether we’re talking about a new musical record or a new set of spark plugs, is always a good thing. Champion claims that their proprietary heat-active alloy allows these plugs to maintain a stable operating temperature regardless of driving conditions.
Spark plugs bragging about a double-platinum feature are what most people consider to be a next-level approach. Featuring platinum on both the center and ground electrodes, this efficient design was envisioned for those of you with a more performance-oriented vision.
The benefits are obvious: enhanced performance, smooth engine operation at all times, and improved fuel efficiency. Set to last longer than your average vehicle, these spark plugs can be yours at less than $5. There is no better time to change your old plugs than now!
NGK Ruthenium HX
Third time’s a charm, at least that’s how the saying goes. NGK seems to have taken over this list, and for good reason. Their reputation is unquestionable, and these particular spark plugs are equally suitable for turbo and direct-injected engines.
Any gasoline-powered engines would benefit from the iconic brand’s Ruthenium HX spark plugs. Designed to handle modern-day stress and urban environments, as well as face expectations such as fuel-efficiency and high-outputs, these plugs promise maximum durability regardless of the car you’re driving.
They will ensure no drop of fuel is left unburnt, a quicker throttle response and improved cold starts. Anti-oxidation capabilities and the ruthenium alloy’s durability make these spark plugs a desirable product.
Ares 11007
Alright, these are not actually spark plugs, but if you decide to replace them yourself you need the complete package. As such, Ares comes in to make your job a lot easier. The removal of aging plugs and installing new ones required the proper tools. Most spark plugs are well hidden, which makes a wrench practically useless.
A special socket comes in handy and the people over at Ares are well aware of that. As such, their 5-unit spark-plug socket set includes spark plugs, an organizer, as well as a 14-mm and an 18-mm socket.
Moreover, these sockets feature a small rubber doughnut inside which will hold the spark plug in place during the installation process. Once you find out this set will cost around $19, you’ll head out and buy one, even if you don’t really need it.
CTA Tools 3235 Gapper
Buying car enthusiasts gifts is relatively easy these days, although the difficult part is making a decision between the plethora of choices on the market. What do you think about a spark-plug gapper that will find its place on a keyring? We have to say a few things about this great tool, a must have in certain situations.
We have mentioned that a required step before installing any spark plug is gapping: be precise, patient, and adjust the distance between the center and ground electrodes – in theory, all modern plugs are delivered ready-to-go, but it might pay off to spend a few seconds and verify the gap before going for the installation process.
Affordable, this tool will prove easy to use, but make sure you consult the specified gap according to the automaker before making any adjustments.
Bosch 4417 Platinum
The Germans at Bosch have been known to innovate and impress the automotive field from time to time – from designing state of the art fuel injectors, to manufacturing all sorts of components for almost all cars out there, the company is always involved in anything car-related.
Regardless of your needs, if the car components bear the brand’s logo, you know you are about to receive a quality product. The same goes for spark plugs, and the innovative design we see here gives credit where credit is due.
The BOSCH 4417 Platinum has been envisioned to look different from other products on the market. German engineers decided upon four yttrium-enhanced electrodes for a better spark and impressive efficiency.
Promising excellent performance sans the use of fancy materials that boost the price up, these plugs are straightforward and will require no adjustments before or after installation. Affordable and reliable, these plugs will be bought once in a lifetime – no more than that.
Denso Platinum 4503 TT
Platinum is the obvious choice if you are looking forward to improved performance. This precious metal allows spark plugs to last longer and deliver improved spark to each of your cylinders.
Designed to offer improved fuel efficiency and quicker response times from the engine, these Denso Platinum TT spark plugs are certainly worth the price. Featuring a platinum-tipped center electrode, and complemented by pure alumina powder insulator, these plugs will handle the stress.
Combining advanced technologies, improved efficiency and performance, and the reputation of one of the biggest names in spark plugs, these plugs are also affordable.
ACDelco Professional Iridium
This pricy offering, coming from ACDelco, shows off a state of the art build. The brand’s Professional Iridium Spark Plugs were designed for long lasting drives, with performance and a smooth running engine in mind.
A high-quality product, this spark plug seems like the ideal choice for most modern vehicles, simply because of the efficient and smaller electrode that ensures a lowered energy consumption.
With a built-in suppressor and pre-gapped delivery these plugs are a success among car owners.
Motorcraft Spark Plugs
Hailing from Motorcraft, this somewhat pricier option is also worth mentioning. Their spark plugs were specifically designed with Ford car owners in mind, in accordance to factory specifications.
Motorcraft promises high-quality spark plugs, similar to the original equipment, that come with a simple installation and longtime usage in mind. Motorcraft plugs are the best choice for your modern Ford car or truck, particularly since we are dealing with a brand known for its top quality control.
Guaranteed to fit your Ford, with a worry-free installation and promising a long life, these spark plugs are usually found in application-specific kits.
Autolite XP Finewire
Promising durability and an impressive lifespan, the Autolite XP Finewire Iridium Spark Plug are technologically advanced and ready to go.
Based around an iridium construction, with great performance and reliability in mind, these spark plugs feature an iridium-enhanced center electrode as well as a 0.6-mm finewire design. They’re complemented by the brand’s proprietary platinum sidewire technology, which makes them functional, performance-oriented and fuel efficient.
Moreover, Autolite backs their plugs with a five-year limited guarantee. That’s one hell of a promise.
E3 Premium DiamondFIRE Electrode
With a long and possibly hard to remember name, the E3 Premium DiamondFIRE Electrode Automotive Spark Plug is unique in many ways. A special patent has been employed in the construction of this particular plug, which offers an innovative design in an effort to offer the optimal spark.
Once fitted to your engine, this spark plug will – in theory – deliver a 6% increase in power. Following years of research and innovation, this plug was designed to increase the combustion pressure by creating the perfect spark, thus resulting in a better power output. Energy-efficient and featuring a diamond shape, this spark plug might just be your new found friend.
Considering it meets OE requirements, most engines will feel pleased with your new acquisition.
NGK 6619
Considered a premium-grade product from NGK, this spark plug will most likely cost more than others. However, it is safe to assume it will be worth it – and it does come as part of a package deal.
Changing all of your spark plugs at once is always a good idea, and this package offers six of them – if that seems like too many, don’t worry. It’s not like these things are going to rust or something. Just store them with the certainty that you won’t be needing other spark plugs any time soon.
Featuring an iridium-based construction as well as an incredibly refined electrode, these efficient spark plugs are a reliable performance-oriented option. Who can say ‘no’ to that?
NGK Laser Platinum
Versatile and suitable for various applications, these spark plugs complete an already impressive NGK lineup. Designed with powerful engines in mind, the Laser Platinum spark plugs are what most users would consider ‘high end’.
Innovative and developed using state of the art technologies, these plugs are highly appreciated by customers and they’re known as the best platinum plugs around. That reputation is backed by laser-welded electrode tips, anti-corrosion attributes and an OEM-approved design.
The NGK Laser Platinum spark plugs were meant for people who enjoy nothing more than a long-lasting, worry-free use. Precise, yet expensive, these spark plugs are one of those go-to options that no one ever regrets.
Autolite APP104 Double Platinum
Based on a thoroughly tested design, these spark plugs were designed to deliver excellence on a daily basis. Compared to the NGK plugs we mentioned earlier, this Autolite option was not meant to stand out from a crowd or improve engine performance. It won’t perform miracles but it will handle its business very well for a long time.
Ideal for that daily commute and your average car, this spark plug uses good materials, modern construction techniques and assembly, and delivers a middle ground between super affordable products and those premium-grade plugs that high performance cars use.
This one’s a no brainer, if you are not willing to waste time and money on a performance-oriented choice that won’t do you any good.
Other Tips
- Have your vehicle information and owner’s manual handy when you’re shopping for new plugs, to make sure the right ones will be fitted to your vehicle.
- Most modern spark plugs were designed to last for a while, some manufacturers promising as many as 100,000 miles without issues. Advanced electrode materials – platinum and iridium – are part of the reasons for such durability, but you shouldn’t wait that long before making a change or going for an upgrade.
- Time and long usage will leave their mark on your spark plugs. Rust and corrosion are even worse, because they make plugs difficult or impossible to remove. Damaging your cylinder head is definitely something no one wants.
- Make sure to purchase the right spark plug type specified by the manufacturer and match the spark plug’s heat range to your vehicle’s engine.
- You should also know that spark plugs used in naturally aspirated engines are very different from the ones fitted to forced-induction engines.
- Gap your spark plugs before installing them. Set the precise distance between the center and ground electrodes before fitting them to your engine.
- It might be a good idea to keep away from plugs that have multiple electrodes.
- Replacing your spark plug wires on a regular basis might also be good idea.
- Never go for the cheapest option. Quality spark plugs will cost a bit more, simply because they offer reliability, optimal fuel economy, and engine performance.
Contents
- Spark Plugs: What To Consider
- Types of Spark Plugs
- Failing Spark Plugs Signs
- How to Change Your Spark Plugs
- New Spark Plugs Benefits
- The 20 Best Spark Plugs:
- NGK Iridium IX
- Denso Platinum 4504 TT
- Bosch Copper with Nickel
- NGK V-Power
- ACDelco 17 Professional RAPIDFIRE
- Champion Copper Plus
- Autolite Copper
- Champion Double Platinum
- NGK Ruthenium HX
- Ares 11007
- CTA Tools 3235 Gapper
- Bosch 4417 Platinum
- Denso Platinum 4503 TT
- ACDelco Professional Iridium
- Motorcraft Spark Plugs
- Autolite XP Finewire
- E3 Premium DiamondFIRE Electrode
- NGK 6619
- NGK Laser Platinum
- Autolite APP104 Double Platinum
- Other Tips
