H2Chief is correct like a motherf*cker on this one.
I just took my truck to the dealer and got my vents adjusted. After reading his post, it made sense why you could clearly smell the exhaust of the car in front of you while the vents were closed
The heat outside was one thing, but I swear you would have seen me on the news for putting a hole in the next stop-light comedian using a musket and a screwdriver, that would see me with all the windows open and call me out for "BUDGET PIMPIN"