Cars are typically the personal space for a few people. Odor control involves eliminating the source of the odor. Unfortunately, the source of the odor may be from the habits of one of the occupants. It does little to remove the smoke odor from the car if one of the occupants keeps smoking. We will operate on the assumption for this article that one of the current occupants is not the source.
The next step involves cleaning the vehicle. It starts with removing trash, clothes, shoes, blankets, etc. The source of the odor could be one of these items. Do not forget the trunk as odors can permeate into the car through the back seats. Vacuum the car thoroughly including the trunk. Clean the soft surfaces using a low moisture and/or extraction system. Some organic liquid spills can benefit from a bacteria treatment. Wipe down the vinyl or leather coverings with appropriate cleaner. Be sure to accelerate drying to prevent growth of mildew. This can be done with fans along with air exchange through open windows.
The final step is to deodorize the vehicle by recreating the conditions of penetration. You can use an odor encapsulant in two ways. Spray down the soft surfaces to immediately remove any remaining odor. Next, you can wet fog with the odor encapsulant and allow the air conditioner to circulate it through the ventilation system. Wipe down any sediment from the windows, vinyl, or leather coverings. At this point, after thorough drying, an ozone machine may be needed to go deeper into the pores of the various surfaces in the vehicle. A dry vapor machine may be another step that adds a fragrance to deal with any psychological responses to the original condition. Simple consumer odor blocks can be used consistently over the life of the car to make the odor part of the distant past.