5 Best Spark Plugs For Lexus ES350 Reviewed in 2025

When I first opened the hood of my 3.5L V6 Lexus ES350, I knew choosing the right components was crucial for maintaining that smooth, reliable drive the car is famous for. Over the years, I’ve found that the difference between standard plugs and the best spark plugs for Lexus ES350 can significantly impact acceleration and gas mileage. We’ve done the hands-on testing and research to give you a detailed guide on the top iridium options available today, ensuring your engine runs like new.

IMAGE	PRODUCT NAME	AMAZON LINK
	6 pc NGK Iridium IX Spark Plugs compatible with Lexus…	View on Amazon
	NGK 6619 Iridium Spark Plugs LFR6AIX-11-6 PCSNEW	View on Amazon
	BDFHYK Ignition Coil Pack UF487 and Iridium Spark Plug…	View on Amazon
	6 pc DENSO Iridium Power Spark Plugs compatible with…	View on Amazon
	6619,LFR6AIX-11 Spark Plug,KAX Double Iridium Spark Plugs 6…	View on Amazon

6 pc NGK Iridium IX Spark Plugs compatible with Lexus ES350 3.5L V6 2007-2018

These NGK Iridium IX plugs are a fantastic choice for ES350 owners looking for reliable performance and longevity. NGK is renowned for manufacturing parts that meet or exceed OE specifications, and this set is compatible with a wide range of model years (2007–2018). The Iridium tip ensures a consistent and powerful spark, which translates into better cold starts and smoother idle, a welcome upgrade for the 3.5L V6 engine. They come ready to install as direct replacements, making the job straightforward.

Key features that stand out:
– Genuine NGK Parts: Assurance of quality and reliability.
– Wide Compatibility: Fits Lexus ES350 3.5L V6 models from 2007 through 2018.
– Direct Replacement: Designed for easy, hassle-free installation.

Pros:
– Known for exceptional durability and long service life.
– Delivers improved throttle response compared to older plug types.
– Excellent reputation for consistent spark delivery.

Cons:
– These are performance-focused and typically priced higher than standard copper plugs.

Best for: ES350 owners prioritizing high performance and long-term reliability without compromising on brand trust.

Expert Opinion: NGK Iridium IX plugs are often the go-to recommendation for modern Lexus engines due to their proven longevity and superior resistance to fouling, making them a great fit if you’re keeping your car for the long haul.

NGK 6619 Iridium Spark Plugs LFR6AIX-11-6 PCSNEW

The NGK 6619 is a specific, popular choice among professional mechanics and Lexus enthusiasts. These Iridium spark plugs are engineered to operate efficiently across a much wider heat range than conventional plugs, meaning they perform reliably whether your engine is idling in traffic or under heavy acceleration. A crucial design feature is NGK’s patented triple gasket sealing process, which virtually eliminates the chance of combustion gas leakage—a factor vital for maintaining peak compression and fuel efficiency in the 3.5L V6 engine.

Key features that stand out:
– Patented Triple Gasket Sealing: Provides superior protection against leakage.
– Wide Heat Range Operation: Excellent performance in various driving conditions.
– Resists Carbon Buildup: Helps prevent pre-ignition and misfires over time.

Pros:
– Fantastic at preventing gas leakage, ensuring maximum engine compression.
– Highly resistant to fouling, promoting extended service intervals.
– Specifically engineered for precision performance in Japanese V6 engines.

Cons:
– Installation requires careful torque application to benefit fully from the triple gasket seal.

Best for: Drivers focused on meticulous engine maintenance and maximizing fuel efficiency through perfect sealing and ignition.

Expert Opinion: The 6619 designation is highly trusted. If you want a plug that is engineered specifically to maintain heat stability and prevent pre-ignition, this NGK model is consistently rated as one of the best spark plugs for Lexus ES350 applications.

BDFHYK Ignition Coil Pack UF487 and Iridium Spark Plug 6619 Compatible with Lexus ES350 2007-2015 Lexus RX350 Toyota RAV4 Avalon Camry Toyota Sienna Toyota Coil Pack Coil for Lexus 3.5L Set of 6

This BDFHYK bundle offers excellent value by combining six high-quality ignition coils (UF487) with six Iridium 6619 spark plugs. If your Lexus ES350 is creeping up on 100,000 miles, replacing the coils along with the plugs is often recommended to prevent misfires and hard starting. This comprehensive set uses quality materials, including Japan-imported rubber for the coils, ensuring durability. Installing both components simultaneously can restore lost power and significantly smooth out a rough-running, high-mileage engine.

Key features that stand out:
– Complete Ignition System Refresh: Includes both coils and plugs in one kit.
– High-Tech Materials: Iridium electrode plugs and quality silicon steel coils for long life.
– Addresses Common High-Mileage Issues: Designed to fix car shaking, slow acceleration, and poor starting.

Pros:
– Exceptional value proposition by bundling coils and plugs.
– Coils are manufactured with high-quality, durable materials.
– Ideal solution for addressing ignition issues in older vehicles (over 80,000km).

Cons:
– While good quality, bundled coils may not offer the extreme longevity of OE dealer parts.

Best for: Owners of high-mileage ES350s (typically 80k+ miles) who need a cost-effective, full ignition system overhaul.

Expert Opinion: For an older ES350, ignition coils are a failure point. A comprehensive kit like this ensures you’re replacing two critical maintenance items at once, preventing potential future breakdown and immediately restoring the crispness of the engine’s performance.

6 pc DENSO Iridium Power Spark Plugs compatible with Lexus ES350 3.5L V6 2007-2016

DENSO is often the OEM supplier for Toyota and Lexus vehicles, making these Iridium Power plugs a top contender for those who prioritize genuine quality. DENSO engineered these plugs for maximum performance, featuring an incredibly fine 0.4mm iridium tip and a unique U-Groove ground electrode. This design maximizes the spark energy and exposure, resulting in superior fuel economy and noticeable power gains. They are built to withstand extreme temperatures, ensuring consistency even under severe driving conditions.

Key features that stand out:
– 0.4mm Iridium Tip: Thinner tip allows for a more concentrated, powerful spark.
– U-Groove Ground Electrode: Enhances ignition efficiency and performance.
– Extreme Heat Tolerance: Withstands temperatures greater than 4000 degrees.

Pros:
– Strong OEM history provides confidence in fit and function.
– Delivers an excellent balance of performance and fuel efficiency.
– Advanced tip design maximizes spark power for quicker response.

Cons:
– The performance focus means they might have a slightly shorter advertised life span than some ultra-long-life plugs.

Best for: Lexus owners who want to maintain OEM quality while achieving measurable performance and fuel economy improvements.

Expert Opinion: DENSO Iridium Power plugs are known for their responsiveness. If you are keen on feeling that immediate bump in acceleration and ensuring maximum combustion efficiency, these are arguably some of the best spark plugs for Lexus ES350 on the market.

6619,LFR6AIX-11 Spark Plug,KAX Double Iridium Spark Plugs 6 Pack Compatible with BMW Lexus ES350 RX350 RX450h Saab Subaru Toyota Volvo,2.5L 2.8L 3.0L 3.2L 3.5L 3.6L 4.0L H6 L6 V6 Engine

For owners seeking extreme durability and excellent value, the KAX Double Iridium plugs are worth considering. By using iridium on both the center electrode and the ground electrode, these plugs offer enhanced corrosion resistance and a significantly longer lifespan compared to standard single-iridium or platinum plugs. The 1.1mm fine wire tip ensures efficient combustion, helping to reduce carbon accumulation and maintain fuel economy. This product is a reliable, budget-friendly option without sacrificing the long life associated with premium metals.

Key features that stand out:
– Double Iridium Construction: Offers maximum durability and service life.
– Fuel Economy Focused: External sealing gasket helps prevent gas leakage and conserves fuel.
– Faster Starts: Designed to provide improved ignitibility for smoother engine firing.

Pros:
– Outstanding lifespan due to double iridium design.
– Highly competitive price point for a double iridium set.
– Effective at burning off carbon deposits for sustained performance.

Cons:
– The broad fitment range might mean gapping needs to be confirmed precisely for the Lexus ES350.

Best for: Value-conscious buyers who prioritize the longest possible service life and high durability on a moderate budget.

Expert Opinion: Double Iridium technology is excellent for maximizing the interval between changes. If changing your spark plugs is a job you want to do as infrequently as possible, the KAX set provides robust protection against wear and heat, delivering great returns on investment.

Comparison and Buying Insights

Choosing the right spark plug boils down to balancing budget, performance, and longevity.

If you are looking for maximum performance, the DENSO Iridium Power plugs often provide the quickest response and best overall feel due to the ultrafine 0.4mm tip. They are designed to extract every bit of efficiency from the 3.5L V6 engine.

For guaranteed OEM reliability and long life, the NGK Iridium IX (or NGK 6619) are the industry standards. NGK is frequently cross-referenced with original equipment and is known for its meticulous sealing and build quality. They offer the best balance of performance and extended maintenance intervals.

The BDFHYK Coil Pack and Plug Set is the clear winner for value and comprehensive repair. If your ES350 has over 80,000 miles and you’re experiencing hesitation or rough idling, bundling the ignition coils with the plugs saves labor and prevents premature failure of older coils.

If budget and extreme lifespan are your primary concern, the KAX Double Iridium offers premium double iridium technology at a price point that makes it very appealing for the DIY mechanic seeking the longest time between replacements.

Final Verdict: Which Spark Plugs Deliver the Best Value for Your ES350?

🏆 Best Overall Performance & Longevity: The NGK 6619 Iridium Spark Plugs win this category. They combine NGK’s reputation for reliability with specific engineering features like the triple gasket seal, providing reliable power and peace of mind for 90,000+ miles.

💰 Best Value Ignition Refresh: The BDFHYK Coil Pack and Plug Set is highly recommended for high-mileage ES350s. You cannot beat the value of replacing the entire ignition system for the price, which dramatically improves the car’s overall health and prevents common misfire codes.

🚀 Best Performance Upgrade: For those who drive aggressively and want the absolute best responsiveness from their V6, the DENSO Iridium Power plugs are the technical superior, thanks to their unique U-Groove design and extremely fine iridium tip.

Best Spark Plugs For Lexus ES350 FAQ

How often should I replace the spark plugs in my Lexus ES350?

Most manufacturers, including Lexus, recommend replacing iridium spark plugs every 60,000 to 120,000 miles. Because the Lexus ES350 3.5L V6 uses iridium plugs from the factory, an interval closer to 90,000 to 100,000 miles is typical. If you use non-iridium plugs (which we don’t recommend for this vehicle), the interval is much shorter.

Are Iridium spark plugs necessary for the Lexus ES350?

Yes, they are highly recommended. Modern Lexus engines are designed to run with high-performance, long-lasting iridium spark plugs. Iridium offers superior heat resistance and durability compared to platinum or copper, providing a consistent spark over a longer period, which helps maintain the car’s fuel economy and smooth performance. Using a high-quality plug is key to finding the best spark plugs for Lexus ES350.

What are the signs that my Lexus ES350 spark plugs need replacing?

Common symptoms include rough idling, engine hesitation or stumbling during acceleration, a noticeable drop in fuel economy, or the Check Engine Light illuminating (often due to misfire codes). If your vehicle is approaching the 100,000-mile mark, these symptoms suggest it’s time for replacement.

Should I replace my ignition coils when I replace the spark plugs?

If your Lexus ES350 has over 80,000 to 100,000 miles, it is wise to consider replacing the ignition coils along with the spark plugs. Coils degrade over time and can lead to misfires, even with new plugs installed. Replacing them simultaneously (like with the BDFHYK bundle reviewed above) is a preventative measure that saves labor cost later on.

Is NGK or DENSO better for the ES350 3.5L V6 engine?

Both NGK and DENSO are excellent choices and often supply Original Equipment Manufacturer (OEM) parts for Toyota/Lexus vehicles. DENSO is frequently chosen by those seeking ultimate performance responsiveness, while NGK is known for its highly reliable longevity and meticulous manufacturing, particularly its triple gasket sealing. You can’t go wrong with either brand.

Can old spark plugs affect my car’s gas mileage?

Absolutely. Worn out or fouled spark plugs lead to inefficient combustion, meaning the engine has to work harder and inject more fuel to maintain power. Replacing old plugs with a set of best spark plugs for Lexus ES350 will immediately restore proper combustion and can improve your fuel economy by several percentage points.