Denso 3484 Spark Plug

Denso Iridium Long Life Spark Plug

Denso 3484 is an Iridium Long Life spark plug built for OE-level performance, durability, and emissions control. It is a direct-fit ignition component for select Toyota and Lexus hybrid applications, including Toyota Camry, Avalon, and RAV4, as well as Lexus ES300h and NX300h models.

The Iridium Long Life (SIP) line focuses on extended service life and stable ignition performance. Denso 3484 uses an iridium center electrode tip, a platinum needle ground tip design, and a copper core center electrode to support consistent spark delivery in demanding secondary ignition systems.

Key Features

• Part number: 3484
• Iridium center electrode tip for long-life ignition service
• Platinum needle ground electrode tip design with needle-to-needle configuration
• Copper core center electrode and nickel ground electrode core material
• 5000 ohm resistance for OE-style ignition circuit performance
• Flat seat design, 14.00 mm thread diameter, 16.0 mm hex size
• Pre-gapped to 0.8 mm
• Manufactured to meet strict OE performance, durability, and emissions standards

Detailed Description

Denso 3484 is an OE-style spark plug for hybrid Toyota and Lexus engines that require precise ignition control and long service intervals. The Iridium Long Life (SIP) product line is engineered for dependable spark stability, while the iridium tip and platinum needle ground design help maintain consistent firing characteristics over time. This spark plug is a strong match for drivers searching for a Denso 3484 spark plug for Toyota Camry, Lexus ES300h spark plug replacement, or a Toyota RAV4 iridium long life spark plug.

This part cross-references DENSO Auto Parts FK16HR-A8 and Toyota 90919-01259 for the same application.

What It Helps Address

• Hard starting caused by worn spark plug electrodes
• Rough idle from weakened ignition output
• Misfire conditions related to spark plug wear
• Reduced fuel efficiency from inconsistent combustion
• Emissions issues tied to degraded secondary ignition performance

Installation Notes and Tips

Verify thread diameter, reach, seat type, and heat range before installation. Denso 3484 uses a flat seat, 14.00 mm thread diameter, 26.50 mm reach, and manufacturer heat range 16. Confirm vehicle-specific service data for torque specification and gap verification, even though the plug is pre-gapped to 0.8 mm. This spark plug is listed for 2012-2017 Toyota Camry, 2013-2016 Toyota Avalon, 2016-2018 Toyota RAV4, 2013-2016 Lexus ES300h, 2015-2017 Lexus NX300h, 2017-2018 Toyota Avalon, 2017-2018 Lexus ES300h, and 2018-2021 Lexus NX300h.

Quality Assurance

Denso manufactures this spark plug to strict OE performance, durability, and emissions standards. The Denso 3484 design reflects OE-style fitment and construction for select Toyota and Lexus applications.