Denso 3356 Spark Plug

Denso Iridium Long Life Spark Plug 3356

Denso 3356 is an Iridium Long Life spark plug built for secondary ignition service in a wide range of import vehicles. It is engineered to meet OE performance, durability, and emissions standards, with an iridium center electrode and a platinum chip ground tip for stable ignition performance.

Compatible With select Hyundai, Kia, Jaguar, and Mitsubishi applications, including Hyundai Sonata, Kia Optima, and Jaguar XJ8 fitments. If you are replacing worn plugs on a 2006-2009 Hyundai Sonata or a 2005-2009 Kia Spectra, this Denso Iridium Long Life plug is built to match the specified application.

Key Features

• Brand line: Iridium Long Life for extended-service ignition applications
• Iridium center electrode tip material for consistent spark delivery
• Platinum chip ground electrode tip design
• 5000 ohm resistance for ignition system compatibility
• Pre-gapped at 1.1 mm
• 14.00 mm thread diameter, 19.00 mm reach, flat seat
• 16.0 mm hex size for standard service tools
• OE-focused construction for durability and emissions control

Product Details

Denso 3356 is a spark plug designed around OE-style specifications, including a copper core center electrode, nickel ground electrode core, and a single standard ground configuration. The Iridium Long Life line is aimed at drivers who want a direct replacement spark plug that follows the original equipment performance targets for ignition stability and service life. This part cross-references DENSO Auto Parts SK16PR-A11 for the same application.

Vehicle coverage includes 2006-2009 Hyundai Sonata, 2006-2009 Kia Optima, 2005-2009 Kia Spectra, 2005-2009 Kia Spectra5, 2005-2008 Hyundai Tiburon, 2007-2008 Kia Rondo, 2003-2007 Jaguar S-Type, 2005-2007 Jaguar Super V8, 2004-2007 Jaguar Vanden Plas, 2004-2007 Jaguar XJ8, 2004-2007 Jaguar XJR, 2007 Jaguar XK, 2005-2007 Jaguar XKR, 2005-2006 Jaguar XK8, 1999-2004 Mitsubishi Montero Sport, 2003 Hyundai Elantra, 2001-2002 Mitsubishi Montero, and 2010 Kia Sportage. The part number 3356 is commonly searched for these OE replacement applications.

What It Helps Address

• Misfires caused by worn or eroded spark plug electrodes
• Hard starting from degraded ignition performance
• Rough idle related to inconsistent spark delivery
• Reduced fuel economy from inefficient combustion
• Emissions concerns tied to aging secondary ignition components

Installation Notes and Tips

Verify thread diameter, reach, seat type, and heat range before installation. Denso 3356 uses a 14.00 mm thread, 19.00 mm reach, flat seat, and manufacturer heat range 16, so matching the OE specification is important for proper fitment. Check the gap against the vehicle service specification before installation, even though the plug is pre-gapped at 1.1 mm. Use the correct 16.0 mm spark plug socket and follow the vehicle manufacturer’s torque procedure.

Quality Assurance

Denso manufactures this spark plug to OE performance, durability, and emissions standards. The Iridium Long Life design is built for consistent service in the listed Hyundai, Kia, Jaguar, and Mitsubishi applications, with construction details selected to support original-equipment requirements.