WASHINGTON (Reuters) - The National Highway Traffic Safety Administration said Monday it is opening a probe into 1.4 million Honda vehicles after reports of serious engine issues.

Honda in November 2023 recalled 249,000 vehicles in the United States with a 3.5 liter V6 engine after the Japanese automaker said a manufacturing defect in the engine crankshaft could cause the connecting rod bearing to prematurely wear and seize, leading to engine failure. NHTSA said it has 173 reports of the issue in various Honda and Acura vehicles from the 2016-2020 model years. NHTSA's probe is to determine the severity of the issue and to determine if the vehicles not included in the 2023 recall should be covered.