NHTSA complaint #11754100

Owner complaint summary

I am writing to formally report a serious and recurring safety defect with my 2025 Acura MDX A-Spec (VIN [XXX]) involving the Auto Idle Stop system. The engine repeatedly fails to restart after the Auto Idle Stop feature shuts it off. When my wife releases the brake pedal (for example, at a traffic light), the vehicle either stalls completely or experiences a major delay before restarting sometimes lasting more than 20 seconds, leaving the my wife unable to accelerate. This creates an immediate and unacceptable safety hazard, particularly in intersections or heavy traffic. I previously brought the vehicle to Acura of Langley regarding this exact issue. Despite that visit, the problem has continued. Most recently, on today, while my wife was driving with my kids, the vehicle again entered Auto Idle Stop at a traffic light. When the light turned green, the engine completely shut off and would not restart for more than 20 seconds. This left her stranded in traffic and unable to move the vehicle, creating a clear risk of collision. This is not an isolated complaint. The National Highway Traffic Safety Administration (NHTSA) has opened Engineering Analysis EA25004 into precisely this condition “No Restart After Auto Start/Stop Engages” affecting, among other models, 2016–2025 Acura MDX vehicles. American Honda has also issued dealer communications specifically seeking 2023–2025 MDX vehicles with client complaints of no auto re-start after Auto Idle Stop for inspection prior to any repair attempts. Class-action investigations and prior litigation involving related Idle Stop failures further underscore the known nature and seriousness of this defect. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)