A P0303 code on your 2019 Ford Explorer indicates that the engine control module has detected cylinder 3 misfires beyond acceptable parameters. This fifth-generation Explorer uses different powertrains than newer models.
2019 Explorer: Final Year FWD Platform
The 2019 Ford Explorer was the final year of the front-wheel-drive-based fifth generation, offering a 3.5L naturally aspirated V6, 3.5L EcoBoost V6, and 2.3L EcoBoost four-cylinder.
3.5L V6 Options
Both naturally aspirated and turbocharged 3.5L V6 engines were available. In the V6, cylinder 3 is on one bank. The EcoBoost version adds turbo complexity.
2.3L EcoBoost
The turbocharged four-cylinder provides efficient power. With four cylinders, each contributes 25% of output. Misfires significantly affect smooth operation.
Higher Mileage Considerations
2019 Explorers have accumulated moderate to significant mileage. Normal wear items may need attention. EcoBoost engines may benefit from carbon inspection.
Proven Platform
The fifth-generation Explorer has proven reliable. Address misfires to maintain dependable operation.