Denso 671-8077 Spark Plug Wire Set

Denso 8mm Spark Plug Wire Set for OE Fit

Denso First Time Fit ignition wire sets are built to match factory-installed wire sets in form, fit, color, and performance. This Denso 8mm spark plug wire set, part number 671-8077, uses silicone spark plug boots and OE-style terminal configurations for a direct replacement on select Ford, Lincoln, and Mercury applications.

Compatible With 1984-1992 Lincoln Mark VII, 1988-1991 Mercury Colony Park, 1989-1991 Mercury Grand Marquis, 1988-1990 Ford LTD Crown Victoria, 1990 Lincoln Town Car, 1984-1989 Lincoln Town Car, 1984-1988 Ford Thunderbird, 1984-1988 Mercury Cougar, 1985-1987 Ford Bronco, 1985-1987 Ford E-150 Econoline, 1985-1987 Ford E-150 Econoline Club Wagon, 1985-1987 Ford E-250 Econoline, 1985-1987 Ford F-150, 1985-1987 Ford F-250, 1984-1987 Lincoln Continental, 1984-1986 Mercury Grand Marquis with EEC IV, and 1984-1985 Ford LTD with EEC IV.

• 8mm insulation outside diameter for OE-style ignition wire routing and fit
• Silicone spark plug boot material for heat resistance and flexibility
• Female spark plug end terminal type and female distributor/coil end terminal type
• 115-degree spark plug end boot angle for applications that require angled routing
• Built to meet or exceed OE/OES standards in construction and performance
• Direct replacement ignition wire set for select Ford, Lincoln, and Mercury vehicles

Product Details

The Denso 8mm wire set is engineered as a First Time Fit replacement, meaning it follows the original wire set’s dimensions and connection style closely. That matters on vehicles such as the Ford F-150, Ford Bronco, Lincoln Town Car, and Mercury Grand Marquis, where correct boot angle, terminal type, and insulation size help maintain reliable spark delivery and clean routing around engine components. Part number 671-8077 is also a practical cross-reference for NAPA Mileage Plus 6718077 for the same application.

Common Ignition Issues This Part Can Address

• Misfires caused by worn or heat-damaged plug wires
• Hard starting related to weak spark transfer
• Rough idle from inconsistent ignition output
• Voltage leakage from cracked or deteriorated wire insulation
• Poor fitment from incorrect boot angle or terminal style

Installation Notes

Verify engine application, model year, and any notes such as EEC IV or California exclusions before ordering. Route each wire to match the original layout, and confirm that the 115-degree spark plug boots seat fully on the plugs and clear nearby components. On vehicles like the Lincoln Mark VII and Ford LTD Crown Victoria, correct wire routing helps prevent crossfire and heat-related wear.

Quality Assurance

Denso First Time Fit ignition wire sets are manufactured to OE-style standards for form, fit, color, and performance. The silicone boot construction and OE-matched terminal design support consistent replacement quality across the listed Ford, Lincoln, and Mercury fitments. Part number 671-8077 is built for direct replacement use on the confirmed applications above.