6 High Performance Ignition Coil for Ford Flex (2013-2019) 3.5L Engine

High-Output Ignition Coils for 2013-2019 Ford Flex (Cyclone / D4)

Replaces the aging factory ignition system to eliminate cylinder misfires and restore throttle response in the Ford 3.5L Cyclone V6 engine.

The Stock Flex Ignition Shortcomings

The 3.5L Ti-VCT V6 in the Ford D4 chassis suffers from a common failure point: the transverse engine orientation creates a high-heat environment, particularly for the rear bank of cylinders (1-3) located near the firewall. Over thousands of heat cycles, the factory epoxy resin in the OEM UF646 coils becomes brittle and develops microscopic fissures. These cracks allow voltage to leak to the cylinder head (arcing) rather than reaching the spark plug. Furthermore, the stock boots often succumb to carbon tracking, where electricity finds a path along the outside of the insulator, leading to the erratic idle, reduced fuel economy, and 'limp mode' events common in high-mileage Flex models.

The Engineering Solution

These high-performance replacement coils are engineered to exceed the thermal stability of factory units. Each coil utilizes high-dielectric strength potting compounds and upgraded internal copper windings to ensure a consistent high-voltage discharge even under heavy load. The boots are manufactured from premium, high-temp silicone that resists ozone degradation and thermal hardening, maintaining a moisture-tight seal against the spark plug porcelain. By increasing the winding density, these coils provide a more robust spark energy, which is critical for maintaining complete combustion and preventing the unburnt fuel scenarios that lead to premature catalytic converter failure. The included dielectric grease serves as a secondary barrier against moisture and oxidation at the terminal contact point.

Technical Specifications

Compatibility

• 2013 Ford Flex 3.5L V6
• 2014 Ford Flex 3.5L V6
• 2015 Ford Flex 3.5L V6
• 2016 Ford Flex 3.5L V6
• 2017 Ford Flex 3.5L V6
• 2018 Ford Flex 3.5L V6
• 2019 Ford Flex 3.5L V6

The Ford Durability Standard

As a vehicle designed for heavy-duty family hauling and long-distance utility, the Ford Flex requires ignition components that can handle the stress of varied payloads and constant thermal fluctuations. These coils provide the electrical precision needed for smooth power delivery and towing reliability without triggering Check Engine Lights (CEL) or electronic interference.