NGK 9998 Spark Plug Wire Set

NGK Spark Plug Wire Set for Nissan D21 and Pathfinder

The NGK Spark Plug Wire Set, part number 9998, is a specific-fit ignition wire set built for select Nissan applications. It uses silicone insulation, a blue outer jacket, and noise suppression construction to support stable ignition performance and cleaner signal delivery.

Key Features

• Specific-fit NGK spark plug wire set for confirmed Nissan applications
• Silicone insulation for heat resistance and durability
• Blue insulation color for easy visual identification
• Noise suppression design to help reduce ignition interference
• Mag (Var. Pitch) core material for ignition signal control
• Insulation outside diameter: 8.00
• Part number RC-NX87 / stock number 9998

Product Details

NGK Spark Plug Wire Set 9998 is part of NGK’s ignition product line, which includes spark plugs, glow plugs, ignition coils, coil-on-plug boots, and wire sets. NGK applies its OE-focused manufacturing experience to replacement ignition components for domestic and import vehicles, with an emphasis on durability and operational performance. This wire set is a direct-fit replacement for 1986-1989 Nissan D21 and 1987-1988 Nissan Pathfinder applications, making it a practical choice when servicing aging ignition wiring on these models.

This part cross-references DENSO Auto Parts (e.g., 671-4200) for the same application.

Common Reasons to Replace

• Engine misfire caused by worn or damaged ignition wires
• Hard starting related to weak spark delivery
• Rough idle from deteriorated wire insulation or internal resistance issues
• Radio or electrical noise from failing suppression components
• Visible cracking, heat damage, or corrosion at the wire ends

Installation Notes and Tips

Verify the vehicle application before installation and route each wire to match the original layout on the Nissan D21 or Pathfinder. Inspect the distributor cap, ignition coil, and spark plugs at the same time, since worn ignition components can shorten wire life and affect performance. Confirm each connection is fully seated to maintain consistent spark transfer.

Quality Assurance

NGK is known for OE-level ignition expertise and manufactures replacement ignition parts to meet durability and performance expectations for everyday service use. This spark plug wire set reflects that OE-focused approach for select Nissan fitments.