NGK 93594 Spark Plug

NGK Laser Iridium Spark Plug 93594

NGK Laser Iridium Spark Plug 93594 is built for OE-style ignition performance with long service life. It uses an iridium fine-wire center electrode, a copper core, and a ceramic insulator to support reliable starts and stable combustion in Ford and Lincoln applications.

Key Features

• Laser Iridium design with a single iridium center electrode for durability
• Fine-wire center electrode helps maintain consistent spark delivery
• Copper core construction helps control heat
• High-grade ceramic insulator supports thermal stability
• Resistor spark plug with 5,000 ohms resistance
• Tapered seat, M14 x 1.25 thread, 5/8 in. hex, and 0.984 in. reach
• Pre-gapped to .032 in. / 0.8 mm
• Part number 93594, service number LTR6GI-8

Product Details

NGK’s Laser Iridium line is engineered for OE applications where consistent ignition performance and long wear are important. The iridium tip is harder than platinum, while the copper core and pure alumina ceramic help manage heat under daily driving and higher-load conditions. This spark plug is a direct-style replacement for a range of Ford Transit-150, Transit-250, Transit-350, Transit-350 HD, Explorer, Expedition, F-150, Flex, Taurus, and Lincoln Navigator, MKS, and MKT applications. Part number 93594 is also identified as LTR6GI-8.

This part cross-references Dorman - HELP 93594 for the same application.

Common Reasons to Replace

• Hard starting or extended crank time
• Rough idle or inconsistent combustion
• Misfire codes related to worn spark plugs
• Reduced throttle response under load
• Service interval replacement on Ford and Lincoln ignition systems

Installation Notes and Tips

Verify the engine application against the vehicle service information before installation. Check the pre-gap specification, thread size, seat type, and reach to confirm the plug matches the cylinder head design. Use proper spark plug socket tools and torque to the manufacturer specification to avoid thread or insulator damage. For Ford Transit, F-150, Explorer, and Lincoln Navigator applications, inspect ignition coils and boots during service to help maintain consistent ignition performance.

Quality Assurance

NGK manufactures Laser Iridium spark plugs to OE-level standards for quality and durability. The iridium center electrode, nickel ground electrode tip, and ceramic insulator are selected to support long service life and dependable ignition performance in factory-recommended service intervals.