Denso 5330 Spark Plug

Denso Iridium Power Spark Plug 5330

Denso Iridium Power 5330 is a tapered-seat spark plug built for drivers who want precise ignition performance and stable combustion. It uses a 0.4 mm iridium center electrode to support quicker flame initiation, along with a Tapercut and U-Groove ground electrode design for consistent spark exposure.

Compatible With classic Ford F-150, Ford Mustang, Chevrolet Camaro, and Pontiac Firebird applications, this plug is also listed across a wide range of GM, Ford, Chrysler, Jeep, and Lincoln vehicles from 1978-1997. The Denso 5330 is a direct-fit ignition service part for many V8 and performance-oriented secondary ignition setups.

Key Features

• Iridium center electrode with a 0.4 mm tip for focused spark delivery
• Tapercut and U-Groove ground electrode design
• 5000 ohm resistor for ignition noise control
• Copper core center electrode for heat transfer
• Nickel ground electrode core material
• Pre-gapped at 1.1 mm
• Tapered seat, 14.00 mm thread diameter, 11.60 mm reach
• 16.0 mm hex size and Manufacturer Heat Range 16

Product Details

The Iridium Power line focuses on compact electrode geometry and efficient spark exposure. On this Denso spark plug, the iridium tip helps maintain a fine firing point, while the copper core supports thermal control under demanding engine conditions. The tapered seat and standard ground configuration make the 5330 a practical replacement for many older domestic applications, including Ford Bronco, Chevrolet Corvette, and Jeep Cherokee fitments listed in the catalog.

This part cross-references DENSO Auto Parts ITF16 for the same application.

Common Problems It Can Address

• Hard starting caused by worn or eroded spark plug electrodes
• Rough idle from inconsistent ignition firing
• Misfire complaints related to aged secondary ignition components
• Reduced throttle response from weak spark delivery
• Maintenance replacement for high-mileage ignition service intervals

Installation Notes and Tips

Verify thread diameter, reach, seat type, and heat range before installation. The Denso 5330 uses a tapered seat and 14.00 mm thread diameter, so it should be matched to the cylinder head specification exactly. Check the pre-gap against the engine requirement before installation, and inspect ignition wires, distributor components, and coil condition at the same time for a complete tune-up.

Fits 1978-1997 Ford F-350, N/A; Fits 1978-1984 Ford Bronco, N/A; Fits 1987-1995 Ford Mustang, N/A; Fits 1978-1992 Chevrolet Camaro, N/A; Fits 1978-1992 Pontiac Firebird, N/A.

Quality Assurance

Denso manufactures the Iridium Power line with a fine-wire iridium center electrode and application-specific plug geometry for consistent ignition service. Part number 5330 is cataloged with detailed dimensional and electrical specifications to support accurate replacement selection across listed Ford, Chevrolet, Pontiac, GMC, Jeep, Lincoln, Buick, Cadillac, Chrysler, Dodge, Mercury, and Oldsmobile applications.