Denso 671-8021 Spark Plug Wire Set

Denso 7mm Spark Plug Wire Set for OE Fit

Denso 671-8021 is a 7mm spark plug wire set built to match the form, fit, color, and performance of the factory-installed ignition wires. It is a direct OE-style replacement for select Chevrolet and GMC trucks and vans, including 1994-1997 Chevrolet P30 and 1994-1997 GMC P3500 applications.

Key Features

• 7mm insulation outside diameter for OE-style ignition wire routing and fit
• Silicone spark plug boot material for heat resistance and flexibility
• Female distributor coil end terminal type
• Female spark plug end terminal type with 180-degree boot design
• Built to meet or exceed OE/OES standards in construction and performance
• Direct replacement for select Chevrolet C2500, C3500, K2500, K3500, G30, P30 and GMC C2500, C3500, G3500, K2500, K3500, P3500 applications

Product Details

The Denso First Time Fit line is engineered for factory-style replacement, and this ignition wire set follows that approach with OE-matched form and performance characteristics. The silicone boot material helps maintain a secure connection at the spark plug end, while the 7mm wire size supports the original routing and fit expected on these Chevrolet and GMC ignition systems. Part number 671-8021 is a practical choice when replacing worn ignition wires on 1994-1997 Chevrolet P30 and 1994-1997 GMC P3500 models, as well as other listed C/K-series and G-series applications.

This part cross-references ACDelco 718C and Bosch 09722 for the same application.

What It Helps Address

• Misfires caused by aged or damaged ignition wires
• Hard starting related to weak spark delivery
• Rough idle from poor wire insulation or terminal wear
• Intermittent ignition performance from cracked boots or degraded connections
• Voltage leakage across worn spark plug wire insulation

Installation Notes and Tips

Verify engine application before installation and route each lead to match the original wire path. Confirm the female terminal ends are fully seated at the distributor coil and spark plug connections, and inspect nearby ignition components for wear before completing the repair. For best results, replace wires on a cool engine and transfer one lead at a time to preserve firing order.

Quality Assurance

Denso First Time Fit ignition wire sets are manufactured to meet or exceed OE/OES standards, with construction intended to match factory-installed parts in form, fit, color, and performance.