Those 140 cars are so airtight they would probably float. There is a big difference in air volume between recirc and fresh air. It is easier to move air inside of a space then to force it in from the outside. I would check that you had proper ventilation out of the car, I think I remember there being some exit flaps in the rear of that car, behind the bumper, but not sure, I haven't had mine for 2 years now. If you have had any mods done to the rear passenger area or had work done on the rear end, and changed any of the airflow exits that could have an effect, but otherwise it is normal. Happy benzing!
Brian

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Brian W. Heitman

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