I have a home ozone generator machine for this, I put it inside the car, close all windows but a small crack, let it run for 20-30 minutes and it will kill any odor, cigarette, dog, barf, BO, you name it. Beware, this acts by oxidizing and killing any organic matter, and with it the smell, this is dangerous to inhale as it will burn your airways and lungs, but doing it with the right precautions, it works wonderfully.