Why does my car smell musty when I turn on the AC?

A musty or mildew smell when you turn on your AC almost always means mold and bacteria growing in the evaporator and ventilation system, often combined with a clogged or dirty cabin air filter. Miami's high humidity is the perfect breeding ground, because moisture condenses on the cold evaporator and never fully dries out, letting mold thrive. Besides the unpleasant smell, this can affect air quality for anyone sensitive to mold. The fix usually involves replacing the cabin air filter and treating the evaporator and ducts with an antimicrobial cleaner, and sometimes clearing a blocked AC drain that lets water pool. Running the fan without AC for a few minutes before shutting off helps prevent it from returning. Motoro Cars cleans and treats your AC system and replaces the cabin filter to restore fresh, clean air across 40+ brands. Book an AC freshening service at motorocars.com or call Wynwood at (786) 634-2002 or Doral at (786) 633-3220.