NHTSA Complaint #11700100 — 2024 ACURA MDX

AC / DEFROSTER / HVAC I am reporting a potential safety and health defect involving the HVAC system in my 2024 Acura MDX. When operating the air conditioning or the front windshield defroster, a strong musty odor enters the cabin. The dealer informed me that resolving the odor requires an EVAP core cleaning, replacement of the cabin filter, and the use of a disinfectant that will be circulated throughout the ventilation system to kill mold, mildew, and other contaminants. I was told this is the “first step” in addressing the issue and that the estimated cost is $440 out of pocket. This is extremely concerning because the presence of mold or bacterial contamination inside the HVAC evaporator and ventilation system affects the air my children and I breathe inside the vehicle. Mold exposure can cause respiratory irritation, allergic reactions, headaches, and other symptoms, especially in enclosed spaces. The HVAC system in this vehicle is a sealed, manufacturer-controlled system which the owner cannot access or service, so this type of contamination should not be considered routine maintenance. I have researched this issue and found that Honda/Acura vehicles have a documented history of HVAC mold and mildew odors, and Honda has previously issued internal investigative bulletins requesting dealers to collect parts from vehicles with musty HVAC smells. There are also mold-related complaints already filed with NHTSA for the 2024 MDX model year. This suggests the possibility of a broader engineering or design issue. I need this issue addressed immediately for health reasons, and I may have to initially pay out of pocket to ensure my family’s safety. However, I believe this is a safety-related defect that Acura should be responsible for correcting, not the customer, especially on a relatively new vehicle still under warranty. I am requesting that NHTSA document this case and consider evaluating whether a pattern of HVAC mold contamination exists in newer Acura vehicles.