Denso 3306 Spark Plug

Denso Double Platinum Spark Plug 3306

Denso Double Platinum spark plug 3306 is built for OE-style ignition performance in a wide range of import and domestic applications. It uses a platinum chip ground electrode, platinum center electrode tip, and a copper core center electrode to support consistent spark delivery and durability.

The Double Platinum line focuses on stable ignition performance and emissions-conscious operation, making it a practical choice for drivers servicing older Mitsubishi Eclipse, Volkswagen Jetta, and Porsche 928 applications that call for this plug specification.

Key Features

• Part number 3306 from Denso Double Platinum
• Platinum chip ground electrode tip design for durable spark performance
• Platinum center electrode tip with copper core center electrode
• Nickel ground electrode core material with standard ground configuration
• 5,000 ohm resistance for ignition system compatibility
• Flat seat design, 14.00 mm thread diameter, 19.00 mm reach
• Pre-gapped at 0.8 mm
• Manufactured to OE performance, durability, and emissions standards

Detailed Description

Denso 3306 is a Double Platinum spark plug engineered for vehicles that require a flat-seat plug with a 14 mm thread and 19 mm reach. The platinum tip materials help maintain consistent firing characteristics over time, while the copper core center electrode supports heat transfer and ignition stability. With a 20.6 mm hex size and 5,000 ohm resistance, this plug is built to match the electrical and mechanical requirements of the listed applications.

Fitment includes 1990-1999 Mitsubishi Eclipse, 1991-1992 Volkswagen Jetta, 1985-1991 Porsche 928, and other applications such as Mazda B2200, Volvo 740, and Volkswagen Passat. This part cross-references DENSO Auto Parts P20PR8 for the same application.

What It Helps Address

• Hard starting caused by worn or fouled spark plugs
• Rough idle from inconsistent ignition output
• Misfire conditions related to degraded plug electrodes
• Reduced fuel economy from weak spark delivery
• Emissions issues tied to aging ignition components

Installation Notes and Tips

Verify thread diameter, reach, seat type, and heat range before installation. Confirm the gap specification against the vehicle service information, even though this plug is pre-gapped at 0.8 mm. Use proper torque procedures for flat-seat spark plugs and inspect ignition wires, coils, and boots during service to avoid repeat misfire concerns.

Compatible With 1990-1999 Mitsubishi Eclipse, 1991-1992 Volkswagen Jetta, 1985-1991 Porsche 928, and other listed applications. Additional fitment includes 1992-1994 Volkswagen EuroVan, 1987-1992 Mazda B2200, 1985-1988 Volvo 740, and 1971-1980 Dodge Colt.

Quality Assurance

Denso manufactures this spark plug to OE performance, durability, and emissions standards. The Double Platinum design reflects Denso’s focus on long-term ignition consistency for service replacement applications.