NGK 4477 Spark Plug

NGK Laser Iridium Spark Plug 4477 Overview

NGK 4477 is a Laser Iridium spark plug built for OE-style ignition performance in a wide range of Ford, Mazda, Mercury, Jaguar, and Aston Martin applications. It uses an iridium center electrode tip, copper core materials, and a tapered seat design to support consistent spark delivery and stable combustion.

As part of the NGK Laser Iridium Spark Plug line, this plug reflects NGK’s OE-focused manufacturing approach and long history supplying original equipment spark plugs for domestic and import vehicles. The 4477 part number is a direct reference point for shoppers searching for an NGK 4477 spark plug for Ford Mustang, Ford Focus, or Ford F-150 service.

• Laser Iridium spark plug with iridium center electrode tip material
• Copper core center and ground electrode materials
• Standard ground configuration with one ground electrode
• Pre-gapped at .052 inches
• 5000 ohm resistance
• 14 mm thread diameter, 5/8 hex size, tapered seat
• OE-style design for selected Ford, Mazda, Mercury, Jaguar, and Aston Martin engines

Detailed Product Description

NGK 4477 is engineered as a Laser Iridium spark plug for vehicles that call for precise ignition performance and OE-equivalent fitment. The iridium tip helps maintain a consistent spark point, while the copper core construction supports heat transfer and dependable operation. With a tapered seat, .708 reach, and 53.00 insulator height, this plug is built to match the specifications required by the listed applications.

Fitment includes 2007-2012 Ford Mustang, 2006-2010 Ford Focus, 2000-2003 Ford F-150, 2003-2005 Mercury Sable, and 2002-2005 Jaguar X-Type, along with additional Ford, Mazda, and Aston Martin applications. If you are searching for an NGK 4477 replacement spark plug for Ford Focus or Ford Mustang maintenance, this part number is commonly referenced for those OE-style service needs.

This part cross-references DENSO Auto Parts 4505 for the same application.

What It Helps Address

• Rough idle caused by worn spark plug electrodes
• Hard starting from weakened ignition output
• Misfire conditions related to plug wear or incorrect gap
• Reduced throttle response from inconsistent combustion
• Service replacement needs on vehicles calling for a 0.044-inch or 0.052-inch gap, depending on application

Installation Notes and Tips

Verify the vehicle-specific gap before installation, since listed applications call for different settings such as 0.044, 0.050, 0.052, or 0.054 inches. Use the notes for your exact year, make, and model, and confirm the tapered seat, 14 mm thread diameter, and .708 reach match the engine specification before installation. For Ford Mustang, Ford Focus, and Ford F-150 applications, follow the gap recommendation listed for the exact model year.

Quality Assurance

NGK is a long-established OE spark plug manufacturer with broad coverage across domestic and import vehicles. The 4477 part number is produced to OE-style standards for durability and operational performance in the applications listed.