Who says that a door seeal to a car is not designed to be airtight?
What rubbish
Go in the greatest storm that you can find and with the water splashing up from deep puddles at speed. Does you door let in the force of the storm? Nah it does not.
Not an iota of draught nor a drop of water comes in, unless it is a really old banger. This car was nearly new.
Of course door seals are designed to be airtight. That is their VERY purpose for their being.
"I recognise this behaviour as the dog indicating scent emitting from the inside of the vehicle through the seal around the door." (MG)
There are several ways to know if you have an airtight car -- and none of them are pleasant. That's because
the passenger compartment of your car is not designed to be airtight. Fresh air comes in the front of the car, circulates through the passenger compartment and leaves the car through exhausters in the rear. If the cabin of a car or truck were truly airtight, the windows wouldn't defrost, it would get unbearably hot in there and anyone inside wouldn't be able to breathe.
When diagnosing car problems, people might say "airtight" when what they mean is "watertight." Sitting inside a car in the pouring rain or a car wash would quickly tell you if you had any leaks in the door or window seals or even unsealed body seams. The vents that allow fresh air to enter and exit have been designed to keep water out and rarely cause auto problems.
http://auto.howstuffworks.com/under-the-hood/diagnosing-car-problems/body/car-air-tight.htmEddie alerted at the passenger door side where scent was escaping from the car. Eddie was correct in his alert at the source of the scent.