Denso 3381 Spark Plug

Reliable Ignition Performance for Select Vehicles

The Denso 3381 spark plug from the U-Groove Conventional line offers dependable ignition for a wide range of vehicles including BMW 328i, Toyota Tacoma, and Honda Civic. Designed with precision materials and a unique U-groove ground electrode tip, this spark plug supports efficient combustion and consistent engine performance.

• U-groove ground electrode tip design for improved spark exposure
• Nickel ground electrode and center electrode tip for durability
• Copper core center electrode for enhanced conductivity
• Standard ground configuration with a single ground electrode
• Flat seat type with 14mm thread diameter and 26.5mm reach
• Pre-gap size of 1.1 mm for optimal ignition timing
• Hex size of 16.0 mm for easy installation
• Manufacturer heat range rating of 20 for balanced heat dissipation
• Resistance of 5000 ohms to reduce electrical interference

About the Denso U-Groove Conventional Spark Plug Line

The U-Groove Conventional spark plug line by Denso features a distinctive U-shaped groove on the ground electrode tip. This design increases the spark exposure area, promoting better ignition and combustion efficiency. The conventional construction combines nickel and copper materials to provide reliable performance and longevity across various vehicle makes and models.

Technical Details and Compatibility

The Denso 3381 spark plug is engineered with a nickel ground electrode core and tip, paired with a copper core center electrode, ensuring effective heat transfer and electrical conductivity. Its flat seat and 14mm thread diameter make it compatible with many engines requiring these specifications. The 1.1 mm pre-gap size is factory set to optimize ignition timing and combustion efficiency. This spark plug is compatible with a broad range of vehicles including BMW 328i, Toyota Tacoma, Honda Civic, Lexus GX460, and Subaru WRX STI, among others.

Common Applications and Problem Solving

• Restores smooth engine starting and idle stability
• Reduces misfires and rough running conditions
• Improves fuel efficiency by ensuring complete combustion
• Minimizes ignition system electrical interference with 5000 ohm resistance
• Supports consistent engine power and acceleration response

Installation Notes and Tips

Before installation, verify the spark plug gap is set to 1.1 mm as specified. Use a torque wrench to tighten the spark plug to the manufacturer’s recommended torque to avoid damage to the threads or seat. The 16 mm hex size allows for standard spark plug socket compatibility. Inspect the spark plug threads and seat for cleanliness to ensure proper sealing and performance.

Quality Assurance and Warranty

Denso spark plugs, including the 3381 part number, are manufactured to meet strict quality standards for durability and performance. The use of premium materials such as nickel and copper ensures long service life. While specific warranty details may vary, Denso products typically come with manufacturer-backed quality assurance to support reliable ignition system operation.