I have a new 2015 infiniti QX50 with only 1000 miles. Sometimes the air that comes in from the vents when the A/C is off or on at low fan smells bad, something like feet! This happens around 20% of the time and it only lasts between 20 seconds and 5 minutes.
I used to park the car for around two weeks under trees. Leaves and little woods covered the hood. It was then cleaned by the dealer and I never parked again under the trees.
The dealer (without any inspection) is suggesting to replace the cabin air filter! But if it is the cabin air filter causing the problem, then the smell would be continuously coming out. However it comes out for a short time then goes away.
What your guess would the problem be? What do you recommend?