Denso 3494 Spark Plug

Denso Iridium Long Life Spark Plug 3494

Denso Iridium Long Life spark plug 3494 is built for OE-level performance, durability, and emissions control in modern ignition systems. It uses an iridium center electrode, a platinum chip ground tip, and a 0.8 mm pre-gap to support consistent spark delivery in demanding daily driving conditions.

Compatible With 2023 Ford Expedition, N/A; 2023 Ford F-150, N/A; 2021-2022 Ford F-150, N/A; and 2013-2014 Hyundai Genesis Coupe, N/A. This part cross-references DENSO Auto Parts ZK20HQR8 for the same application.

Key Features

• Iridium center electrode tip material for stable ignition performance
• Platinum chip ground electrode tip design for extended service life
• Nickel ground electrode core and copper center electrode core for efficient conductivity
• 5000 ohm resistance for ignition system noise suppression
• Flat seat, 14.00 mm thread diameter, 26.50 mm reach, and 16.0 mm hex size
• Manufacturer heat range 20 with a standard ground configuration

Product Details

Denso’s Iridium Long Life line focuses on long-service spark plug construction for OE-style replacement needs. Part number 3494 is engineered to meet strict original-equipment standards for performance, durability, and emissions, making it a direct-fit choice for select Ford F-150 and Ford Expedition applications as well as the Hyundai Genesis Coupe. The iridium center electrode and platinum ground tip help maintain consistent ignition characteristics over time, while the specified pre-gap and resistance support reliable operation in properly matched systems.

Common Issues This Spark Plug Can Address

• Rough idle caused by worn or inconsistent spark plugs
• Hard starting related to weak ignition output
• Misfire conditions from degraded plug electrodes
• Reduced fuel economy from inefficient combustion
• Loss of throttle response from aging secondary ignition components

Installation Notes and Tips

Verify engine application by year, make, model, and OE part number before installation. Check the specified gap and compare it to the vehicle service information before use. Inspect ignition coils, boots, and related secondary ignition components during replacement to avoid repeat misfire concerns. Use proper torque procedures for the flat-seat design to help prevent thread or sealing damage.

Quality Assurance

Denso manufactures this spark plug to OE performance, durability, and emissions standards for consistent replacement quality. Part number 3494 is built for controlled ignition performance in select Ford and Hyundai applications.