I think that the good doctor needs to make SURE that the HVAC setting, whether heat or cold, is set to get outside air. Don’t want to recirculate that smoke through the fan.
MB is right, you doofuses! You need positive airflow THROUGH the car, so clean air has to come in somewhere. Then if the driver’s window is cracked, you get flow from the AC vents, past the stinko cigar, and right out the window. And when you come to a stop, make sure the AC is on full blast, because you won’t be getting the suction from speed.
I concur that the most important aspect of venting cigar smoke is the selection of air flow source. If you have your air flow set on re-circulate, the smoke will not likely vent out the windows properly. If you pull outside air into the car, the cabin will vent properly to expunge the smoke.
In some cars, when the AC is turned on, an amount of re-circulated air is mixed with outside air, which will minimize the venting through a cracked window. Try cracking the rear passenger side window if this happens, it will help vent the car.