How can I remove the bad odor in my car that accidentally sank in the flood?

It wasn't the flood of hurrican katrina, in new orleans, was it? if so, i would burn the vehicle because of the bacteria.

You might have mold and the black mold can kill ya. Do'nt take a chance and if you have the money, go and have the carpet taken out and replaced with new or used carpet. If it's in your seats and the cushions are effected with mold then you have a problem there to and it to has to be either replaced or if minor then just cleaned. Get advise from an interior car professional from the company your car is made. Hope this helped.

You can try shampooing the interior floors and seats with ammonia, it will not cause any discoloration and is strong wnough to get rid of bacteria as well as dilute odors. then you may want to shampoo the interior afterwards with some type of upholstery shampoo with a nice odor this will not take all the odor away but will help to diminish it . You may ahve to so it more than one time to get a better result as dampness is a hard odor to get rid of. I had the same problem with my vehicle ina flood and this is the method I used and I even took it to a car wash with spray deodorizer and sprayed that on the floors and seats after I was done with the whole process. Lots of luck.

If your car was flooded toss the old carpets. Period! Most new cars have up to 4" of foam on the carpet backs and the carpet them selves are coated with a water proof backing so anything you do on the surface will not get to the real problem below (the foam). The carpet layer it self will appear dry while in fact it is only trapping the moisture underneath. Also, many new cars have a fire-wall insulation that is installed prior to many of the dash components. This can be a real issue as it can not be removed without pulling the entire dash and many of the ducting/steering and electrical components. Depending on the vehicle this may be cause for your insurance company to total your vehicle. If it is just carpet or seats spend the money on a good used carpet or go a little deeper and buy new OEM, Odds are that your Insurance company will cover the cost as it is a serious problem and one that can have serious health risks with the Mold.

If it's been flooded, I wouldn't worry about the interior. Have you replaced the ENTIRE electrical system, ECU and all? Start from there and then, once you;re sure that the car will run long enough to justify the deep-cleaning, you can follow the housekeeping hints mentioned elsewhere.

No sense de-funking a car that's going to die ;)

Gut the interior! Junk yards are riddled with cars with good interior. Ebay is a great place to look for seat etc. Usually just a few bots too.