The 2019 Ford Explorer represents the final year of the fifth-generation platform, offering the 3.5L V6 and 3.5L EcoBoost V6 options. When P0306: Cylinder 6 Misfire Detected appears, your Explorer has identified combustion problems specifically in cylinder 6 of the V6 engine.
Final-Year Fifth-Gen V6 Options
The 2019 Explorer offers the naturally aspirated 3.5L V6 (290 hp) and twin-turbo 3.5L EcoBoost V6 (365 hp). Both position cylinder 6 on the rear bank of the transverse-mounted engine. The EcoBoost variant experiences additional turbo heat stress, while both engines use direct injection with potential carbon buildup concerns.
Common P0306 Causes at This Age
Ignition coil degradation from years of operation affects rear cylinders more significantly. Spark plugs approaching service life produce inconsistent combustion. Direct injection allows intake valve carbon accumulation over time. EcoBoost turbo heat accelerates component wear. Fuel injector flow may decrease from deposits. Vacuum leaks develop in aging intake components.
Diagnostic Approach
Identify your engine (naturally aspirated vs. EcoBoost) as diagnosis differs slightly. Scan for all codes—EcoBoost models should check turbo-related faults. Inspect cylinder 6's ignition coil for wear or damage. Remove and evaluate spark plug condition against mileage and service history. Test fuel injector operation. Consider carbon buildup assessment on high-mileage examples. Perform compression testing.
End-of-Generation Considerations
The 2019 Explorer may have significant mileage. Comprehensive ignition service combined with addressing any carbon concerns provides the best long-term reliability.