Smoke smell

[Vasudivan Sunappan <svdivan@xxxxxxxxxxxxx>]

While driving on my 97 318i, my wife frequently complained of exhaust smoke
smell. I immediately pressed the 'Circulation Mode' button, which cuts off
external air intake. The smoke stopped from entering the car and the air
felt fresher. I agreed with my wife after driving right behind very smoky
vehicles like diesel powered engines. Each time I see heavy smoke from the
car in front, I will press the Circulation Mode button. 

My car is two years old now and this smoke smell only happened in the past 6
months. I feel this is rather unusual. Is something gone wrong with
air-conditioning filter? Please share your experience.

SV Divan
GM stay out of BMW!!!!

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