On Monday, the National Highway Traffic Safety Administration (NHTSA) announced that it would be expanding its Investigation into late-model Fords equipped with EcoBoost engines. What initially started as a probe into 2021 model-year Broncos equipped with 2.7-liter turbocharged engines has evolved into a much broader look into several other models and the larger 3.0-liter EcoBoost motor.

Last summer, the NHTSA was prompted to launch an investigation into 2021 Ford Broncos after nearly 30 complaints were issued about the 2.7-liter motor cutting out at highway speeds. This was accompanied by a few petitions demanding the agency take action, prompting the NHTSA to launch a formal investigation. At the time, regulators were fretting over the possibility of “catastrophic engine failure” due to a presumed defect with the intake valves.

While the investigation has been ongoing, it has reportedly started roping in other models and Blue Oval’s larger 3.0-liter turbo used widely in its lineup. According to Reuters, the NHTSA Office of Defects Investigation upgraded the investigation late last week to include an engineering analysis of the 2021-2022 Ford Bronco, Edge, Explorer, and F-150 — in addition to the 2021-2022 Lincoln Aviator and Nautilus — equipped with either the 2.7 or 3.0-liter EcoBoost.

The NHTSA cited 328 customer complaints and 487 warranty claims relating to the vehicles under investigation. However, there have been no injuries associated with any of the above. This brings the total number of vehicles being looked into from roughly 25,000 to a whopping 708,000.

From Reuters:

Ford told NHTSA the defective valves were manufactured out of an alloy known as "Silchrome Lite" that can become "excessively hard and brittle if an over-temperature condition occurs during machining of the component."

Ford said a design change in October 2021 changed the intake valve material to a different alloy. Ford added it believed "defective intake valves commonly fail early in a vehicle’s life and has suggested that the majority of failures have already occurred."

While we don’t have all the necessary information, it sounds like someone decided to use cheaper materials on the alloy intake valves and it just didn’t work out. Since exhaust values are subjected to significantly higher temperatures, automakers know they can get away with something a little less robust on the intake side. Other automakers have used Silchrome intake valves in the past (often with hardened tips to improve durability) to help reduce manufacturing costs. But exhaust values are always made out of steel boasting higher temperature strength and resistance.

Implemented correctly, the above shouldn’t be much of an issue. But we’ve seen companies swap in underperforming parts after the vehicle designs have been completed in a bid to save money — sometimes to catastrophic effect. That seems a plausible scenario here based on the information provided by the NHTSA and Ford. However, we’re going to have to wait and see what regulators say after the investigative probe has concluded.

"During the investigation, multiple contributing factors were identified, which can lead to the fracturing of the intake valves in the subject engines," NHTSA said in a document pertaining to the investigation. "Ford acknowledged that a fractured intake valve can result in catastrophic engine failure and a loss of motive power and noted that following a valve fracture, a vehicle typically requires a full engine replacement."

This is a bummer for Ford, which has clearly been attempting to improve its reputation for reliability. Truth be told, this has become an issue for several brands — perhaps even the industry as a whole, if we consider how recall frequencies have jumped in recent years. But Ford has been eager to move away from any unpleasant associations. Just about everyone I’ve spoken to from the company in 2023 has said this has become their biggest priority.

My guess is that this will turn eventually into a formal or voluntary recall. While repairing the alleged defect is likely to be a costly endeavor for Ford, having it go unaddressed (assuming the NHTSA even leaves that as an option) may mean having to replace engines as more broken valves are sucked into the engine. That’s not going to help alleviate any consumer fears regarding the reliability of Blue Oval’s products and may end up being most costly in the long run.

[Image: Ford Motor Co.]

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