The National Highway Traffic Safety Administration has closed its investigation into over 400,000 Ford SUVs and pickup trucks over a loss of motive power.  The probe was opened in 2022 over concerns with a faulty valvetrain in certain Bronco vehicles equipped with 2.7L EcoBoost engines, after increasing complaints from Bronco customers. The NHTSA later expanded the investigation to include the Edge, F-150, Explorer, Lincoln Aviator and Nautilus, all equipped with the same motor.

Back in August Ford filed documents with the NHTSA, releasing a statement that the company was aware of 811 warranty claims associated with fractured intake valves on 2021-2022 Bronco models. The automaker began its investigation into the valvetrain issue in January 2022 following 22 complaints of engine failure after three months or less involving Lincoln Aviator and Nautilus models equipped with the 2.7- or 3.0-liter EcoBoost engines. Ford reported that the engine intake valves may fracture while driving, potentially causing engine damage and a sudden loss of drive power.

Since August the automaker has been working on a fix involving dealers inspecting each potentially faulty model by determining their cumulative number of engine cycles, then replacing engines that don't pass that inspection. Interim letters, notifying owners of the safety risk, were mailed October 17, 2024. 

Ford is also extending warranty coverage on the vehicles for a period of 10 years or 150,000 miles, whichever occurs earlier.