Best Spark Plugs: Keep Your Engine Purring With These Top Picks

You replace your spark plugs fairly often, so it’s important to know which ones are superior.

byZach Faulds|
Engine & Motors photo

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BYZach Faulds/ LAST UPDATED ON June 5, 2023

Many car owners take the mighty spark plug for granted. It's a simple yet crucial device that's responsible for delivering the spark that ignites the fuel mixture in your engine. There's more to it than that, though. Your engine needs a spark plug that offers the right temperature, gap, and fit to ensure the best performance of your engine. Once you figure out those basic details, you need to find out what's the best spark plug within those parameters. That's the part we're here to help you sort out with our recommendations for the best spark plugs.

Best Overall
NGK Iridium IX Spark Plug

NGK Iridium IX Spark Plug

Summary
The best spark plugs for performance, power, efficiency, and reliability.
Pros
  • A good design that is unlikely to misfire or malfunction
  • Superb performance and efficiency
  • Long lifespan
Cons
  • On the pricey side for a spark plug replacement
Best Value

Denso Platinum TT Spark Plug

Summary
An affordable platinum spark plug that delivers great durability and performance for your dollar.
Pros
  • Excellent price
  • Durable, double platinum tip for enhanced performance
Cons
  • Gap is occasionally set incorrectly
  • Performance isn’t on par with iridium spark plugs
Honorable Mention

Bosch Copper with Nickel Spark Plug

Summary
These plugs boost cold starts, enhance fuel ignition, and foster optimum performance, reliability, and heat transfer.
Pros
  • Long lifespan
  • May increase gas mileage and boost performance in certain vehicles
Cons
  • Factory set gap may not be correct
  • May not fit all vehicles listed in the specs

Summary List

Our Methodology

Spark plugs are crucial to the safe, clean, and trouble-free operation of any car. Though modern spark plugs are incredibly long-lasting, reliable, and come in a huge range of predetermined fitments, they will still need to be changed eventually. So we researched all of them to find the best ones to choose for your car, and made decisions based on that research and our personal experience with these brands of spark plugs.

Best Spark Plugs Reviews & Recommendations

NGK 6619 Iridium IX Spark Plugs snagged the top pick in our spark plug comparison because they offered the best mix of high-performance, fuel efficiency, durability, and dependability. Featuring an iridium construction, these high-quality spark plugs provide a longer lifespan than copper and platinum spark plugs.


Its ultra-fine electrode wire promises superior fuel efficiency as well as silky-smooth engine idle and response. You can also expect a healthy boost in power and torque, thanks to the optimal air-fuel mixture that these iridium spark plugs generate. It receives top marks for durability too, with such impressive features as metal plating to resist corrosion and seizing, as well as a long insulator nose to prevent fouling.

Pros

A good design that is unlikely to misfire or malfunction

Superb performance and efficiency

Long lifespan

Cons

On the pricey side for a spark plug replacement

If you’re in the market for solid all-around spark plugs that are easy on your wallet, look no further than Denso 4504 PK20TT Platinum Spark Plugs. These value-priced platinum plugs pack a lot of performance, efficiency, and durability for a downright reasonable price.


Featuring a dual-platinum construction, with a platinum disc and platinum electrode tip, these spark plugs provide a reliable spark to generate smooth, reliable combustion of the air-fuel mixture. This translates to great engine dependability, fuel efficiency, and performance. Another impressive feature is purified alumina powder, which is used as an insulator to increase thermal conductivity for maximum longevity.

Pros

Excellent price

Durable, double platinum tip for enhanced performance

Cons

Gap is occasionally set incorrectly

Performance isn’t on par with iridium spark plugs

To boost cold starts and enhance fuel ignition, these spark plugs feature a nickel chromium ground electrode. They have a heavy-duty yttrium enhanced copper core center for optimum performance, reliability, and heat transfer.


These plugs are very durable and have a long lifespan. The nickel-plated shell provides anti-seize and corrosion protection. No gapping is required, and the plug's ribbed insulator prevents flashover. The plugs remedy misfires in certain vehicles, can increase mileage in some vehicles, and may boost performance by a noticeable amount.

Pros

Long lifespan

May increase gas mileage and boost performance in certain vehicles

Cons

Factory set gap may not be correct

May not fit all vehicles listed in the specs

This OE replacement plug has a long lifespan and is very durable. The iridium firing pin is welded with a 360-degree continuous laser, and the copper core is designed to reduce fouling. The wire is ultra fine, and the nickel-plated shell prevents it from seizing. No gapping is required, and the plug has corrosion protection.


One of the best things about these plugs is that they last a long time, which is important if you have an engine in which the plugs are difficult to access. While you may not notice a change in mileage when you install them, you may see a boost in performance. They are also very reliable, and you don't need a special gap tool for installation.

Pros

Excellent durability

Pre-gapped for many applications

Cons

Compatibility must be double-checked

The Champion Copper Plus Spark Plug is a versatile option available to purchase in a value four-pack. This product features a nickel alloy center and a ground electrode that provides reliability and durability. The copper included in the center electrode allows for an increase in conductivity and heat control than your average, everyday spark plug. This spark plus makes an excellent choice for all types of automotive engines, particularly older models. In addition to vehicle engines, this spark plug can be used in lawn and garden applications and smaller engines. Make sure to consult your vehicle's owner's manual or instruction manual for your equipment before using these spark plugs as a replacement in your engine.


One downside is that it is not an ideal option for many new vehicles and newer engines. Always make sure to consult your manual or contact your vehicle manufacturer before attempting to install new spark plugs.

Pros

Affordable

Great Performance for older engines

Cons

Not optimal for many newer engines

Our Verdict

For a high-quality spark plug, consider the NGK 6619 Iridium IX Spark Plugs, featuring excellent performance, power, efficiency, and reliability. Or, choose the Denso 4504 PK20TT Platinum Spark Plugs, an affordable platinum spark plug that delivers excellent durability and performance.

What To Consider When Choosing Spark Plugs

Key Features 

Heat Range 

Keeping a spark plug at the optimal heat range is extremely important to performance and engine health. To cool and the plug will foul up and fail to run properly, and too hot will lead to detonation or pinging. Which heat range will work for your engine depends on a few factors, with boost and compression being the biggest players in most cases. For factory vehicles, using the heat range suggested by the plug manufacturer will usually suffice. However, those who have modified their vehicle will likely use that suggestion as a starting point, using different combinations of plug heat ranges until they find what works. 

Electrode Material

Spark plugs feature a center and side electrode to create the spark. The center electrode almost always features a copper core with a nickel, iridium, or platinum coating on the tip. The coating is there to protect the electrode because it is more resistant to the conditions inside the combustion chamber, effectively extending plug life. A lot will determine which material is best for your vehicle, but iridium or platinum is generally better for modern commuting vehicles. Nickel, often called copper for simplicity, plugs are better for older and higher-performance applications. This is because copper plugs, while plagued by the shorter life span, can throw a stronger spark and maintain cooler temperatures. 

Thread Pitch and Reach 

Not all spark plugs are the same dimensions because not all engines place the same demands on these aspects of the plug. You want to make sure that whatever plugs you consider fit what the vehicle calls for. Thankfully, these are standardized, with only a few options to select from, and all you need to do is match thread pitch and reach to ensure a plug will physically work for your engine. 

 FAQs

You've got questions. The Drive has answers.

Q: How can you tell when spark plugs are operating at optimum temperature?

If you are wondering how to tell whether your spark plugs are operating well before problems arise, look at their color. Usually, when the spark plug is a light tan or gray color, that should tell you that it is running at optimum temperature. In other words, your vehicle’s engine is in good condition.

Q: How frequently should I change my spark plugs?

This depends on the quality of spark plugs you have in your car. Top-quality spark plugs will last longer than lower-quality plugs. Most mechanics recommend you change your copper core spark plugs every 30,000 miles or every 50,000 miles for iridium core spark plugs. This interval may be shorter if your engine isn’t in top condition, so it’s vital to inspect your spark plugs for premature wear and change them accordingly.

Q: Will a faulty spark plug turn on the check engine light?

When your vehicle has a faulty spark plug, it can cause the check engine light to illuminate, signaling an issue. In some instances, the check engine light may even be flashing instead of a solid light. When the warning light appears, it is essential that you or a professional mechanic look into the cause. 

Q: What are the symptoms of a faulty spark plug?

You may notice the following symptoms if your spark plugs need to be replaced: hesitation or backfiring during acceleration, decreased acceleration, rough idle, spark plug wires charred on the end that goes onto the plugs, a significant drop in fuel economy, and difficulties starting your engine. If your ride doesn’t run as well as it usually does, and you suspect it’s attributed to bad spark plugs, inspect the plugs yourself or have a mechanic do it.

Why Trust Us

Our reviews are driven by a combination of hands-on testing, expert input, “wisdom of the crowd” assessments from actual buyers, and our own expertise. We always aim to offer genuine, accurate guides to help you find the best picks.

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