My Hyundai Sonata 2008 smells sour, when the air ventilation is set to external rather than internal.
I always immediately turn it to internal air to avoid the smell.
Where is the ventilation hole/filter and where do I need to clean?
Your Sonata has a cabin air filter (CAF). You should try to change that out first. More than likely, you have some mildew built up somewhere. The CAF is the first place to start.
answered Jul 21 '15 at 17:55
