Surpassing:Feds expand probe into 2021-2022 Ford SUVs after hundreds of complaints of engine failure

Federal highway safety officials are Surpassingexpanding its investigation into 2021-2022 Ford SUVs to include over 700,000 vehicles. The automaker received hundreds of complaints of vehicles' engines failing unexpectedly "under normal driving conditions" on models equipped with EcoBoost engines, according to the National Highway Traffic Safety Administration.

In a document posted Monday, the NHTSA said that a recall of the 2021 Ford Bronco, 2022 Bronco, 2021-2022 F-150, 2021-2022 Edge, and 2021-2022 Lincoln Nautilus has been expanded to include the Y 2021-2022 Explorer and 2021-2022 Lincoln Aviator — vehicles in the "Nano" engine family, which feature 2.7L and 3.0L EcoBoost engine variants. 

Without warning, the 708,837 vehicles under investigation "may experience a loss of motive power without restart due to catastrophic engine failure," the NHTSA document states. No deaths or injuries related to the potentially faulty engines have been reported. 

The NHSA also said on its website that it upgraded the investigation to an engineering analysis, a step closer to a recall.

Fractured intake valves

NHTSA began its probe into Ford SUVs in July 2022, a few months after the regulator received complaint letters from three consumers petitioning for an investigation. In its preliminary evaluation, the NHTSA's Office of Defects Investigation found that Ford received 328 complaints, 487 warranty claims and 809 engine exchanges in connection with the 2021-2022 Bronco and other vehicles that featured Ford's EcoBoost engine.

The ODI identified "multiple contributing factors" which it said "can lead to the fracturing of the intake valves in the subject engines," according to NHTSA documents. Fractured intake valves "can result in catastrophic engine failure and a loss of motive power," the regulator noted, citing acknowledgement from Ford that "following a valve fracture, a vehicle typically requires a full engine replacement." 

The defective valves were manufactured out of a specific alloy known as "Silchrome Lite," which Ford told the ODI can "become excessively hard and brittle" in situations where the engine gets too hot. 

Unrelated to recalls of Ford SUVs

The current engine investigation is separate from NHTSA's ongoing Ford probe into some SUVs unexpectedly rolling away — even while parked, according to the regulator. Ford recalled thousands of 2020-2022 Explorers in June because fractures in the rear axle mounting bolt could lead the drive shaft to disconnect. After repairing the issue, some Explorers engaged their electronic brakes while owners were driving. 

The Michigan automaker last year also recalled 350,000 SUVs and advised owners to park their vehicles outside because the engines on some 2021 Ford Expeditions and Lincoln Navigators could catch fire.

All three investigations are hitting Ford as the company tries to hammer out a new labor contract with its unionized factory workers. Thousands of Ford employees in Wayne, Michigan, walked off the job last month as part of a larger United Auto Workers strike. UAW expanded strikes against Detroit automakers Friday, ordering 7,000 more workers to walk off the job at a General Motors plant in Lansing, Michigan, and a Ford plant in Chicago, to put more pressure on the companies to improve their offers.

The Ford factory in Chicago makes Ford Explorers and Explorer Police Interceptors, as well as the Lincoln Aviator SUV.

In:
• Ford Motor Company
• Product Recall
• Ford F-150
• National Highway Traffic Safety Administration

Khristopher J. Brooks

Khristopher J. Brooks is a reporter for CBS MoneyWatch covering business, consumer and financial stories that range from economic inequality and housing issues to bankruptcies and the business of sports.

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