Moldy Interior - what should i do?

My kids spilt milk in the backseat of my Toyota Corolla. We used bleach several times to try to clean it out, baking soda and even went to a professional to get it cleaned. Nothing works and it still smells horrid. Even though i open the windows every night to air it out. Think the entire right back seat is molded through. I have two young kids and think its bad for them to inhale all the mold spores. Any advice? Should i keep trying to clean it myself? Replace the back seats? sell the car? If you think it should replace the car seats can you advice how i would do that? How much it would cost. Please be as detailed as possible i have little experience with cars. Thanks a lot!

I would not worry too much about mold spores. There are thousands of kinds of mold and only a fraction of them are allergenic and only a handful are toxic.

Did you pull the seat out to clean it? People spill milk and worse things in cars all the time. Remove the seat. Use a furniture attachment on a carpet shampoo machine. Once it dries, it should not be noticeable.

Unless they spilled gallons of milk, it’s unlikely that there’s enough down there to support a mold colony large enough to be hazardous. Is it possible that something else is stinking? Have you tried hosing it with Lysol to the point where the seat is sopping? (if you do this, leave the windows open to air out before you drive it, plus keep in mind that Lysol contains alcohol and if you use enough the vapors could become flammable)

Are you sure the smell is in the rear seat? Usually these smells disappear over time. How long has it been since the “incident”?

You can easily remove the entire rear seat. It is possible to buy them from the junk yard/auto recycler and replace it especially with a common Corolla. They usually unbolt which maybe should be done anyway to clean it. You find rememinents underneath of milk residue that actually smell. Or it may be in the carpet matting itself. Use your nose as your guide.

You could take it to an automotive reupholsterer and have the foam and seat cover replaced.

If you’ve worked with upolstery before, you could even buy the foam adding and covers and replace them yourself. It isn’t rocket science, but it does involve some elbow grease and a few special tools to deal with the clips. The tools are not expensive.

Most cars the rear seat bottom pulls out with with very little effort. I would remove the seat bottom, inspect to make sure the milk was contained only in the seat cushion. If the smell is gone with the seat bottom removed, I would then simply replace the entire seat bottom with one from a auto recycler, AKA junk yard.

Its only a Corolla, if it was my car I wouldn’t even be concerned if the bottom seat upholstery matched so long as the smell is gone, and the seat is usable.