Denso 5313 Spark Plug

Denso Iridium Power Spark Plug 5313

Denso Iridium Power spark plug 5313 is built for drivers who want precise ignition performance and stable combustion response. It uses a 0.4 mm iridium center electrode to support efficient spark delivery, along with a tapercut, U-groove ground electrode design for consistent firing characteristics.

Compatible With Saab 9-5, Saab 9-3, Saab 900, Saab 9000, and Porsche 911 applications listed below, this Denso spark plug is a direct-fit secondary ignition component for select performance and OE-style service needs.

• Iridium center electrode tip material for fine-wire ignition performance
• 0.4 mm center electrode for focused spark delivery
• Tapercut, U-groove ground electrode tip design
• Copper core center electrode and nickel ground electrode core materials
• 5000 resistance specification
• Flat seat type with 14.00 mm thread diameter and 19.00 mm reach
• Pre-gapped to 0.8 mm
• 16.0 mm hex size for service access

Iridium Power Product Line

Denso Iridium Power is the brand line focused on fine-wire iridium ignition technology. The smaller iridium center electrode helps support reliable spark initiation, while the electrode geometry is engineered for efficient flame kernel development in the combustion chamber. Part number 5313 is part of that line and is also referenced as Denso Auto Parts IQ22.

This part cross-references Denso Auto Parts IQ22 for the same application.

Detailed Product Description

Denso 5313 is an iridium spark plug for secondary ignition systems that require a flat-seat plug with a 14.00 mm thread diameter and 19.00 mm reach. The iridium tip and tapercut, U-groove ground design are intended to support stable ignition performance under demanding operating conditions. It is listed for 1999-2003 Saab 9-5, 1999-2002 Saab 9-3, 1985-1998 Saab 900, 1989-1998 Saab 9000, and select 1989-1993 and 1991-1992 Porsche 911 applications. For Porsche 911 fitment, the listing notes that two spark plugs are required per cylinder.

Common Issues This Part Can Address

• Worn or eroded spark plug electrodes
• Misfire caused by degraded ignition performance
• Hard starting related to weak spark delivery
• Rough idle from inconsistent combustion
• Reduced throttle response from aged plugs

Installation Notes and Tips

Verify the vehicle application against the listed fitment before installation. Confirm the 0.8 mm pre-gap, 14.00 mm thread diameter, 19.00 mm reach, and flat seat type match the engine specification. Use proper spark plug service procedures and torque to the vehicle manufacturer’s specification. For Porsche 911 applications, follow the note that two spark plugs are required per cylinder.

Quality Assurance

Denso manufactures this spark plug to published dimensional and material specifications, including iridium center electrode construction, nickel ground electrode material, and the stated resistance value. Part number 5313 is built for the listed Saab and Porsche applications and is identified in interchange data as Denso Auto Parts IQ22.

• Fits 1999-2003 Saab 9-5, N/A
• Fits 1999-2002 Saab 9-3, N/A
• Fits 1985-1998 Saab 900, N/A
• Fits 1989-1998 Saab 9000, N/A
• Fits 1989-1993 Porsche 911, N/A, Two spark plugs are required per cylinder.
• Fits 1991-1992 Porsche 911, N/A