U.S. launches investigation into 1.4 million Honda vehicles over engine issues

The National Highway Traffic Safety Administration (NHTSA) has begun investigating reports of major engine troubles with 1.4 million Honda vehicles, the agency said Monday. Also included in this probe are various Honda and Acura models from the 2016 to 2020 model years and follow an November 2023 recall of 249,000 vehicles in the United States with 3.5 liter V6 engines.

Honda recently recalled an engine crankshaft manufacturing defect that could cause the connecting rod bearing to wear prematurely or seize, could cause engine failure. In vehicles not part of the recent recall, the NHTSA has received 173 reports of similar engine failures. The agency is trying to find out just how serious the problem is and whether the recall should be widened to cover other vehicles.

The investigation affects several models: From model 2016-2020 Acura MDX, 2018-2020 Acura TLX, 2016-2020 Honda Pilot, 2017-2019 Honda Ridgeline and 2018-2020 Honda Odyssey models. NHTSA said that all of the reported incidents have engine failure characteristics in common with the recent recall but do not fall into the current coverage.

Honda said it was aware of the investigation and is working with the agency. A Honda spokesperson said that the agency’s spokesperson “has already been in communication with us on this and we will be in communication throughout the query process as well.”

It was only this month that the Japanese automaker first disclosed it had been investigating the issue since 2020, and said it received 1,450 warranty claims around that time regarding the recall. The recall covers Honda dealers who are instructed to inspect affected vehicles, and repair or replace engines as necessary.

NHTSA's probe underscores the agency’s commitment to addressing potential safety risks, particularly in cases where manufacturing defects may affect a large number of vehicles. If the investigation reveals additional risks, it could lead to a broader recall impacting even more Honda and Acura owners across the United States.