theres probubly something like what your looking for. try a search engine. its likely the stock air handling system and the fan in particular cant pull air thru a filter of the type needed to get rid of smells like your talking about. the flow of air would be reduced due to the added restriction. another option might be a device like ionic breeze, these were sold in sharper image and they did have a cig lighter / power port car version. the full size home versions do work well to remove dust oders and smells. the car models im not so sure of, and they wouldnt do much for continuios smells comming in from the outside though they might reduce the smells quicker. obvious alternative is adding scent devices or hanging pine tree smelling dodads to your mirror.