NHTSA opens investigation into engine failures in some 2021 Ford Bronco models

After receiving several complaints, the National Highway Traffic Safety Administration (NHTSA) has opened an investigation into reports of “catastrophic engine failures” in V6-powered variants of the 2021 Ford Bronco. The issue could affect over 25,000 units of the SUV.

The agency’s Office of Defects Investigation (ODI) began evaluating the issue in May 2022. It met with Ford representatives the following month and learned that the engine failure some Bronco owners have reported is due to a valve keeper-related problem. In short, the keeper doesn’t hold the retainer in place, which allows the valve spring to come loose and causes the valve to come in contact with the piston.

“Under normal driving conditions without warning the vehicle may experience a loss of motive power without restart due to catastrophic engine failure related to an alleged faulty valve within 2.7-liter EcoBoost engines,” the NHTSA wrote in a document published in July 2022.

The NHTSA estimates that 25,538 examples of the 2021 Bronco could be affected by the problem. It’s important to note that only V6-powered models are included in the investigation; the 2.3-liter four-cylinder engine is not part of it. And, the investigation is not a recall. Its stated goal is to “assess the scope, frequency, and potential safety-related consequences of the alleged defect.”

Ford hasn’t commented on the investigation. It previously pointed out the five-year, 60,000-mile powertrain warranty covers engine failures.