Q. My Infiniti G37x sedan developed a vinegar smell when using the air conditioner or the heater. The car was in for service, and the dealership replaced the cabin air filter and sprayed something into the heater. It was fine for a few days, but now the smell is back. What could this be? Is the heater or air conditioner leaking? What should the dealer repair shop do now to eliminate the vinegar smell?
A. The smell could be a result of mold/mildew buildup in the climate control system. The first thing you can try is to always use the climate control on the fresh air setting. The recirculate setting tends to build up moisture, which turns into mold. At this point I would go back to the dealer that performed the repair and see if they can do some additional cleaning and spray some more cleaner into the system. In the very worst case, the system would need to be disassembled and cleaned.
John Paul is AAA Northeast’s Car Doctor. He has over 40 years of experience in the automotive business and is an ASE certified master technician. Email your car question to firstname.lastname@example.org.