Denso 5376 Spark Plug

Denso Iridium Power Spark Plug 5376

Denso Iridium Power spark plug 5376 is built for precise ignition performance in high-demand engines. It uses a 0.4 mm iridium center electrode to promote consistent spark delivery, along with a tapercut and U-groove ground electrode design for efficient flame initiation.

Compatible With Ferrari 348 TB, Ferrari 512 TR, Ferrari 348 GTB, Ferrari 512 M, and Ferrari 348 Spider applications, this Denso spark plug is a direct-fit ignition service part for select mid-1990s Ferrari models.

Key Features

• Iridium center electrode with a 0.4 mm tip for focused spark delivery
• Tapercut, U-groove ground electrode design
• Nickel ground electrode core and copper center electrode core
• 0.9 pre-gap size for specified ignition setup
• 5000 resistance rating
• Flat seat, 12.00 mm thread diameter, 19.00 mm reach, and 18.0 mm hex size
• Denso Iridium Power line for performance-oriented ignition service

Product Details

Denso Iridium Power 5376 is engineered around a fine-wire iridium center electrode to help maintain a stable spark under demanding operating conditions. The tapercut and U-groove ground electrode profile supports efficient ignition at the plug gap, while the copper core helps manage heat transfer through the plug body. This spark plug cross-references DENSO Auto Parts IX24B for the same application and is listed for Ferrari 348 TB, Ferrari 512 TR, Ferrari 348 GTB, Ferrari 512 M, and Ferrari 348 Spider fitments.

Common Issues This Part Helps Address

• Misfire caused by worn or eroded spark plug electrodes
• Hard starting from weak or inconsistent ignition output
• Rough idle related to degraded spark quality
• Loss of throttle response from aged ignition components
• Service replacement for plugs that no longer hold the specified gap

Installation Notes and Tips

Verify the specified 0.9 pre-gap before installation and confirm the plug matches the vehicle’s thread diameter, reach, seat type, and hex size. Use the correct torque procedure for the cylinder head material and inspect ignition wires or coils during spark plug service. For fitment, this part is listed for 1990-1992 Ferrari 348 TB, 1992-1993 Ferrari 512 TR, 1993-1994 Ferrari 348 GTB, 1994-1995 Ferrari 348 Spider, and 1995 Ferrari 512 M.

Quality Assurance

Denso manufactures the Iridium Power line with a fine-wire iridium center electrode and application-specific construction for consistent ignition service. Part number 5376 is cataloged for select Ferrari applications and built to the published specifications shown above.