Car windows left down in the rain then car closed up for a week. BAD M

Wash the interior etc,down with white vinegar and water,allow to dry,insert open boxes of baking soda,get damp rid will will draw more moisture out.

Ugh. This is a tough one. First you need to get it dried out as much as possible. Leave all windows down and in the hot sun as much as possible or pull into your garage and put a box fan pointing inside overnight. Would be best to wear gloves and a face mask as you deal with the mold. It can make you sick! Bleach does not kill mold, but there are other cleaners that do. There are lots of ideas on the internet. Here's a good article about cars and mold:

https://www.yourmechanic.com/article/how-to-remove-the-smell-of-mold-from-your-car

Wipe everything down with straight vinegar, then again with a clean damp towel. Wear a face mask and eye protection. Carpeted floor will be the hardest. After you have aired it out and cleaned all the surface mold, take to a professional detailer as they have the right equipment to clean the carpets. Have the car completely detailed on the inside. Be sure to tell them the story, as the employees should take precautions. It will cost a bit more, but well worth it for health reasons.

Moldy can be scary. This is one situation where I might hire a pro to remove it. Let that car air out, for sure. We just went through this with our basement because of floodin, so I definitely feel for ya!

Take it to a professional car cleaner, they deal with that type of problem often. Mold is difficult to get rid of if you don't use a cleaner that will kill the mold.

A professional is needed for that.

Get it professionally detailed. The mold may be deep into the foam rubber under the seat fabric and pros have special solutions and gear to remove it..

Load the car up with newspaper.....and leave it for a while....weeks if need be.....it'll absorb the moisture and most of the smell.