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.
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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.
NGK Iridium IX Spark Plug
- A good design that is unlikely to misfire or malfunction
- Superb performance and efficiency
- Long lifespan
- On the pricey side for a spark plug replacement
Denso Platinum TT Spark Plug
- Excellent price
- Durable, double platinum tip for enhanced performance
- Gap is occasionally set incorrectly
- Performance isn’t on par with iridium spark plugs
Bosch Copper with Nickel Spark Plug
- Long lifespan
- May increase gas mileage and boost performance in certain vehicles
- Factory set gap may not be correct
- May not fit all vehicles listed in the specs
Summary List
- Best Overall: NGK Iridium IX
- Best Value: Denso Platinum
- Premium Pick: Bosch Copper
- Most Durable: Bosch Copper with Nickel
- Best Value Runner-Up: Champion Copper
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
Copper
Copper core spark plugs are the most basic and affordable type of spark plug that you can buy. These used to be the most common plug type on the market, but have recently been replaced by platinum and iridium spark plugs due to their superior performance, efficiency, and lifespan. While many modern engines simply cannot run copper spark plugs, there are a number of older engines that run better using copper plugs.
Platinum
Platinum plugs deliver enhanced performance and fuel efficiency compared to copper plugs, but for a considerably cheaper price than iridium spark plugs. Much like iridium plugs, platinum spark plugs operate at a lower temperature than copper spark plugs. They can also last up to twice as long as basic copper plugs.
Iridium
The best spark plugs on the market boast an iridium construction. Iridium spark plugs give you even better gas mileage, performance, reliability, and longevity than double-platinum plugs. Due to the advanced material and innovative technology integrated into iridium spark plugs, these plugs are priced higher than copper and platinum options. Iridium spark plugs are perfect to use on high-performance engines.
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 long do spark plugs last?
The life-span of spark plugs varies by both manufacturer and vehicle. Yet, the spark plugs in most vehicles sold on the market today should last for 100,000 or more miles. To ensure you do not go past your spark plugs interval, research the type of spark plugs to learn whether they are suitable for your vehicle. Keep in mind that the spark plugs in most performance and luxury models tend to have shorter intervals.
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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