The National Highway Traffic Safety Administration (NHTSA) has launched an investigation into certain Honda and Acura vehicles following reports that their engines fail to restart automatically after stopping at traffic lights or intersections.
The probe, initiated on March 26 by the agency’s Office of Defects Investigation (ODI), centers on Honda’s Auto Idle Stop (AIS) system, which is designed to improve fuel efficiency by shutting off the engine at complete stops and restarting it when the driver accelerates.
The investigation covers several Honda and Acura models, including the 2016-2025 Honda Pilot, 2018-2025 Honda Odyssey, 2019-2025 Honda Passport, 2020-2025 Honda Ridgeline, 2015-2025 Acura TLX, and 2016-2025 Acura MDX. ODI has received at least 1,384 complaints about the issue, some of which allege that a jump-start was required to continue driving. In total, an estimated 2.2 million vehicles are under scrutiny.
There have been four reported incidents where this problem led to a crash or vehicle fire, as well as two reports of injuries. The car company previously issued service bulletins in January 2023 to address the issue, but the NHTSA continues to receive complaints, including from owners who had the recommended service performed.
The agency has now escalated the probe to an engineering analysis, which could take up to 18 months. This process will determine whether a recall is necessary and evaluate the effectiveness of Honda’s previous service measures.
Earlier this year, Honda announced it was recalling 294,612 vehicles in the U.S. due to a software error that can cause the engine to stall or lose power, increasing the risk of a crash.
The National Highway Traffic Safety Administration (NHTSA) posted a notice blaming the issue on a faulty software program in the fuel injection electronic control unit (FI-ECU). The recall affects:
2022-2025 Acura MDX Type-S
2023-2025 Honda Pilot
2021-2025 Acura TLX Type-S
