Glow plug harness failure is quite common for high mileage 7.3L and 6.0L Powerstroke models. Although many owners will find this harness damaged while performing other engine maintenance, sometimes a hard cold start is an early indicator that the harness has begun to fail. Years of supporting high amperage glow plug draw combined with high engine bay temperatures will melt the plastic connectors, eventually resulting in shorts within the circuit. Using our extensive experience with the Ford Powerstroke, our team identified the need for a more durable and economical replacement for the factory harness. This full replacement kit includes everything you need to restore the glow plug wiring harness. Our kit uses high-quality connectors, robust terminals, and superior seals ensuring years of reliable service. As with all our products, this glow plug harness kit includes our signature Mishimoto Lifetime Warranty.