Try to check some of these tips :
The smell can be caused by too much dirt in the car cabin. Now, remove dust or dirt by using a vacuum. Make sure you can reach the corners of the hardest in the vehicle cabin.
Or at least, stop smoking in the car. Because cigarette smoke can go anywhere, including car air conditioning duct. If already, then try to spray fragrance on your intake valves. It is expected the smell of fumes may shift to smell the fragrance.
Baking soda has sufficient ability to remove odors. If you spill something on the carpet, try to sprinkle baking soda on it. Cover and let stand for a few hours. Baking soda will absorb odors. After a few hours, suction baking soda by using a vacuum.
Yes, you read that right. Charcoal not only have the function to cook, but he also has the ability to absorb odors. That is why it is often found in a few charcoal air filter. Well, now take charcoal, put in the car a few days and you will find car smell is lost because it is absorbed by the charcoal.
Use air freshener
If your car smell, you probably still have not put in the car air fresheners. Try using air freshener. If you want to try a natural smell, try placing the coffee because the smell of coffee will descend cabin.
Send to professional
This may be done for odors that are too severe. It may be expensive, but at least it smells like the smell of secondhand severe flooding can be reduced.