Keep it fresh / clean like you do a fridge. Open a box of baking soda. Let it sit 24/7. Mix it up every now and then, replace when necessary. If that doesn't get rid of the smell, pour it right on the seats then leave it over night, then vacuum it out. When we needed to get it out of my bro's car, we took it to a super car place and they cleaned the inside, like legit cleaned. Smelled so much better after