Denso
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Set (8pcs) Denso Iridium Long Life Spark Plugs Stock 3421 Iridium Core .043(1.1mm) Gap Size
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Set (8pcs) Denso Iridium Long Life Spark Plugs Stock 3421 Iridium Core .043(1.1mm) Gap Size
The patented DENSO Spark Plug enables complete fuel ignition in the combustion chamber. It virtually eliminates erratic starts caused by poor fuel mixtures and excessive soot buildup. The DENSO Spark Plug employs a unique ground electrode designed to generate a larger spark nucleus at the point of ignition. Greater spark energy means improved flame travel, producing more complete, consistent, and efficient combustion
Set (8pcs) Denso Iridium Long Life Spark Plugs Stock 3421 Iridium Core .043"(1.1mm) Gap Size
Item #: 60960975

Set (8pcs) Denso Iridium Long Life Spark Plugs Stock 3421 Iridium Core .043"(1.1mm) Gap Size

90% of respondents would recommend this to a friend

Item #: 60960975

PHP 6065

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The patented DENSO Spark Plug enables complete fuel ignition in the combustion chamber. It virtually eliminates erratic starts caused by poor fuel mixtures and excessive soot buildup. The DENSO Spark Plug employs a unique ground electrode designed to generate a larger spark nucleus at the point of ignition. Greater spark energy means improved flame travel, producing more complete, consistent, and efficient combustion
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What Stands Out

Long Lifespan
Designed for durability, these spark plugs ensure a longer operational life, reducing the need for frequent replacements and improving vehicle performance over time.
High Performance
The iridium core enhances combustion efficiency, resulting in better fuel economy and increased engine power compared to standard spark plugs, catering to high-performance vehicle demands.
Precise Gap Size
With a .043" (1.1mm) gap, these spark plugs provide optimized ignition, ensuring smoother engine starts and better throttle response under diverse driving conditions.

Product Details

Shop Set (8pcs) Denso Iridium Long Life Spark Plugs Stock 3421 Iridium Core .043(1.1mm) Gap Size online at a best price in Philippines. B0721V9JYZ
Brand NameDenso
Manufacturer Part Number3421
UPC042511034211
Unit Count1 Count
OEM Equivalent Part Number12 12 0 037 663, 30650843-0, 32 01 0632, 22401 AA580, MN158596, 12 12 2 158 253, 22401-5M016, 55 56 4748, 90919-01191, 30751806-0, 31216183-0, 12 12 0 032 138, 90919-A1002, 12293-PHM-A01, 12565996
Included Components3421
Item Weight15.36 ounces (435.46 grams)
ManufacturerDenso
Model Number3421
Thread Size14
Compatible with Vehicle TypeCar, Truck
Automotive Fit TypeVehicle Specific Fit
Gap Size0.04 inches (0.1 cm)
Core MaterialIridium
Top Material TypeIridium
BrandDenso
Vehicle Service TypeCar, Truck

Who Should Buy?

Suitable For
  • High-Performance Vehicles

    Ideal for owners seeking improved engine performance and efficiency in high-performance or modified vehicles for better acceleration.

  • Long-Distance Drivers

    Perfect for those who frequently drive long distances, as these spark plugs provide extended life and reliability.

  • Mechanics and Professionals

    Recommended for professional mechanics looking for durable spark plugs that ensure optimal engine performance for clients.

Not Suitable For
  • Budget-Conscious Buyers

    Not suitable for those looking for cheaper alternatives, as these spark plugs come at a premium price point.

Product Description

Set (8pcs) Denso Iridium Long Life Spark Plugs Stock 3421 Iridium Core .043"(1.1mm) Gap Size

Have any Query? Chat with us

Customer Questions & Answers

  • Question: What are Denso Iridium Long Life Spark Plugs?

    Answer: Denso Iridium Long Life Spark Plugs, such as Stock 3421, are high-performance spark plugs designed for enhanced ignition efficiency and longer lifespan. The iridium core provides superior conductivity and durability compared to standard copper plugs, allowing for optimal engine performance under various conditions. These spark plugs are ideal for drivers seeking to improve fuel efficiency, reduce emissions, and enjoy smoother rides. Their fine wire design creates a 0.43 mm gap that delivers a reliable spark for ignition, making them suitable for a variety of vehicles.
  • Question: How often should I replace my Denso Iridium Spark Plugs?

    Answer: Replacement intervals for Denso Iridium Spark Plugs vary based on your vehicle make and model, but generally, they last longer than traditional spark plugs. Typically, you should check your spark plugs every 60,000 to 100,000 miles. Signs that they need replacing include engine misfires, rough idling, or decreased fuel efficiency. Using these long-life plugs can also lead to fewer replacements, making them a cost-effective choice for maintaining engine performance.
  • Question: What is the benefit of using iridium in spark plugs?

    Answer: Iridium spark plugs, like the Denso Iridium series, offer several benefits over conventional spark plugs. The high melting point of iridium allows for consistent performance under extreme temperatures, ensuring stable and efficient ignition. Additionally, their finer center electrode improves spark efficiency, leading to better fuel combustion. This results in improved horsepower and torque, making iridium plugs a smart choice for performance vehicles or regular commuters seeking reliability and efficiency.
  • Question: Can I install Denso Iridium Spark Plugs myself?

    Answer: Yes, you can install Denso Iridium Spark Plugs yourself, provided you have basic mechanical skills and the right tools. The process involves removing the engine cover, disconnecting the ignition wires, and unscrewing the old plugs with a spark plug socket. After cleaning the area and checking the gap of the new plugs, you simply screw them back in and reattach the ignition wires. This DIY approach is not only rewarding but can also save you money on labor costs.
  • Question: What gap size is recommended for Denso 3421 spark plugs?

    Answer: The Denso 3421 Iridium Long Life Spark Plugs come with a pre-set gap size of 0.0431 inches (1.1 mm). This fine gap size is optimized for enhanced ignition efficiency, resulting in better combustibility of fuel within the engine. However, it's important to confirm that this gap meets your vehicle's specifications, which can usually be found in the owner's manual. Using the specified gap ensures optimal vehicle performance and fuel efficiency.
  • Question: Are Denso Spark Plugs compatible with all vehicles?

    Answer: Denso Spark Plugs are designed to be compatible with a wide range of vehicles, but it's essential to check your vehicle’s specifications to ensure proper fitment. Different engine types may require specific spark plug models with different dimensions or gap sizes. Using the correct model ensures compatibility and performance, allowing you to achieve maximum engine efficiency. Always refer to your owner’s manual or consult with a professional if you're uncertain about compatibility.
  • Question: What are signs of faulty spark plugs?

    Answer: Signs that your Denso Spark Plugs may be faulty include engine misfires, difficulty starting the engine, rough idling, decreased acceleration, and poor fuel economy. If you notice any of these symptoms, it’s advisable to inspect and possibly replace the spark plugs. Though Denso Iridium Spark Plugs offer extended life, external factors such as oil leaks or fuel quality can still impact performance, so regular checks are recommended.
  • Question: Can using high-performance spark plugs improve my car's efficiency?

    Answer: Absolutely! High-performance spark plugs, like the Denso Iridium series, are designed to optimize combustion efficiency in your engine. The iridium core and precise gap size enhance the ignition process, which can lead to better fuel efficiency and reduced emissions. When installed in vehicles, these spark plugs typically result in improved throttle response and smoother operation, making them an excellent investment for both everyday driving and spirited performance.
  • Question: What maintenance should I perform with Denso Spark Plugs?

    Answer: While Denso Iridium Spark Plugs are low-maintenance due to their long lifespan, periodic inspections are important. You should check for signs of wear, such as carbon buildup or electrode erosion. Also, ensure that the gap size remains consistent with specifications. For optimal performance, consider replacing them according to the manufacturer’s recommendations or if any performance issues arise. Additionally, keeping the engine clean and using quality fuel can enhance the longevity of your spark plugs.
  • Question: Where can I buy Set 8pcs Denso Iridium Long Life Spark Plugs Stock 3421 in Philippines?

    Answer: You can purchase the Set of 8pcs Denso Iridium Long Life Spark Plugs Stock 3421 from Ubuy in Philippines. Ubuy offers a variety of Denso products, ensuring that you get authentic parts delivered directly to your doorstep. Their platform provides multiple payment options and often features customer reviews to help inform your buying choices, making it a reliable source for your automotive needs.

Denso Spark Plugs 3421 Editorial Review

The Denso Iridium Spark Plugs seem to be a great choice for those looking to replace their spark plugs. The product is compatible with a 2016 Tundra 5.7L flex fuel type, according to a FAQ. Customer reviews suggest that the spark plugs have improved their truck's performance, and they appear to be as good as the ones that required replacement at 120k miles. The corrosion-resistant iridium material of the plugs could be beneficial, with one reviewer stating that they could wait until 150k miles before replacing them again. Overall, the Denso Iridium Spark Plugs have received positive feedback and seem to be a reliable option for those in need of a new set.

Customer Reviews & Ratings

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Pros

  • Compatible with 2016 Tundra 5.7L flex fuel type
  • Improved truck performance, according to some customers
  • Corrosion-resistant iridium material could be beneficial

Cons

  • No negative feedback was given, so no cons were provided.

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Order now and get it around Wednesday, September 09

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Features & Benefits

  • Patented DENSO Spark Plug enables complete fuel ignition and virtually eliminates erratic starts
  • Unique ground electrode generates larger spark nucleus, improving flame travel for more complete and consistent combustion
  • Greater spark energy improves fuel efficiency, ignition, and reduces emissions
  • Ground electrode developed to improve ignitability for increased efficiency in emission gas purification and fuel consumption
  • DENSO is a reliable and quality brand recognized by the automotive industry
  • DENSO Spark Plug is 100% pre-fired to ensure reliable operation and lasts twice as long as conventional plugs

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