Denso 3416 Spark Plug

Denso Iridium Long Life Spark Plug 3416

The Denso 3416 is an Iridium Long Life spark plug built for OE-level performance, durability, and emissions control. It uses an iridium center electrode tip with a platinum chip ground electrode design to support consistent ignition in demanding daily driving conditions.

The Iridium Long Life product line focuses on extended service life and stable spark performance for vehicles that call for a precise factory-style plug. This Denso spark plug 3416 is a direct-fit option for select Toyota, Lexus, Geo, and Toyota-based applications, including Toyota Corolla, Toyota Celica, Toyota MR2, Lexus LS400, and Geo Prizm fitments.

Key Features

• Iridium center electrode tip for precise spark delivery
• Platinum chip ground electrode tip design
• 5000 ohm resistance for ignition system compatibility
• 0.8 mm pre-gap size for factory-style setup
• 14.0 mm thread diameter with flat seat design
• 19.0 mm reach and 16.0 mm hex size
• Copper center electrode core and nickel ground electrode core
• Manufactured to OE performance, durability, and emissions standards

Product Details

Denso 3416 is engineered as an Iridium Long Life spark plug for vehicles that require a flat-seat, 14 mm plug with a 19.0 mm reach. The iridium tip helps maintain consistent ignition characteristics, while the platinum chip ground electrode design supports long-term wear resistance. This part cross-references Denso Auto Parts SK20R8 for the same application.

Compatible With select 1990-1996 Toyota and Lexus applications, including Fits 1995-1996 Lexus LS400, N/A; Fits 1991-1995 Toyota MR2, N/A; Fits 1990-1993 Toyota Celica, N/A; Fits 1990-1992 Geo Prizm, N/A; and Fits 1990-1991 Toyota Corolla, N/A. Toyota Corolla, Toyota Celica, and Toyota MR2 owners searching for Denso 3416 spark plug replacement can use this OE-style part for the listed applications.

Common Issues This Part Can Address

• Hard starting caused by worn spark plug electrodes
• Rough idle from inconsistent ignition output
• Misfire conditions related to plug wear or gap drift
• Reduced fuel efficiency from weak spark performance
• Emissions concerns tied to degraded ignition quality

Installation Notes and Tips

Verify thread diameter, reach, seat type, and pre-gap size against the vehicle’s service specifications before installation. Use the correct torque procedure for the cylinder head material and inspect ignition components such as wires, coils, and boots during replacement. For Toyota Corolla, Toyota Celica, Lexus LS400, and Toyota MR2 applications, confirm the exact year and engine configuration against the fitment list before ordering.

Quality Assurance

Denso manufactures this spark plug to strict OE performance, durability, and emissions standards. The 3416 is built for factory-style fitment and consistent ignition performance in the listed applications.