Denso 3401 Spark Plug

Reliable Ignition Performance for Honda Accord and Fit

The Denso Iridium Long Life spark plug 3401 is engineered to provide consistent ignition and durability for Honda Accord and Fit models. Designed with advanced materials and precise specifications, this spark plug supports efficient combustion and engine performance.

• Iridium center electrode tip for enhanced durability
• Platinum chip ground electrode tip for stable ignition
• Thick nickel ground electrode core for improved wear resistance
• Copper center electrode core for optimal conductivity
• Pre-gap size of 1.3 mm for precise spark delivery
• Flat seat type with 14 mm thread diameter and 19 mm reach
• Hex size of 16.0 mm for easy installation
• Manufacturer heat range of 20 suitable for Honda applications

Detailed Features of the Denso Iridium Long Life Spark Plug 3401

The Denso Iridium Long Life spark plug 3401 incorporates a fine iridium tip on the center electrode, which offers a high melting point and resistance to wear, ensuring long service life. The ground electrode features a platinum chip tip and a thick nickel core, enhancing ignition stability and durability. The copper core center electrode improves thermal conductivity, helping to dissipate heat efficiently. With a pre-gap size of 1.3 mm and a single ground electrode configuration, this spark plug is optimized for reliable spark generation. The flat seat design and 14 mm thread diameter with a 19 mm reach ensure proper fitment and sealing in compatible Honda engines.

About the Iridium Long Life Product Line

The Iridium Long Life line by Denso focuses on delivering extended durability and consistent ignition performance through the use of iridium and platinum materials. This product line is designed to meet the demands of modern engines by providing stable spark delivery and resistance to electrode wear, which helps maintain engine efficiency over time. The 3401 spark plug is part of this line, offering a balance of longevity and reliable ignition for Honda Accord and Fit vehicles.

Applications and Common Issues Addressed

• Compatible with Honda Accord and Honda Fit models requiring a 14 mm thread spark plug
• Helps resolve misfires caused by worn or damaged spark plugs
• Improves cold start performance and throttle response
• Reduces fouling and electrode wear in high-heat conditions
• Supports consistent combustion to prevent rough idling

Installation Notes and Tips

When installing the Denso 3401 spark plug, ensure the engine is cool to avoid damage to the threads. Use a torque wrench to tighten the spark plug to the manufacturer’s recommended specifications to prevent over-tightening or under-tightening. Verify the pre-gap size of 1.3 mm before installation, adjusting if necessary to match vehicle requirements. The 16 mm hex size allows for standard spark plug socket compatibility, facilitating straightforward replacement in Honda Accord and Fit engines.

Quality Assurance and Warranty

Denso manufactures the 3401 spark plug to meet strict quality standards, ensuring reliable performance and durability. The use of iridium and platinum materials contributes to extended service life compared to conventional spark plugs. While specific warranty details may vary, Denso products typically come with manufacturer-backed quality assurance to support customer confidence in fitment and function.