What the HELL is that smell!?

So, I moved a bag I had thrown on the floor in the backseat after the flood, and realized it was soaking wet underneath. But, I didn't think it was that big of a deal, since it was just a plastic grocery bag and it was on the rubber floor mat.

But, then, as I was driving to school, I was assaulted by a foul smell. It kinda smelled like spoiled milk? Anyway, when I got home, I figured I'd better get the bag off the floor and let the mat dry. I had planned to also Febreze the car from front to back, just for an added bonus.

Well, imagine my surprise when I moved the rubber mat and saw that the carpet mat under it was wet. Then, imagine my horror when I realized that the actual carpeting in the car was sopping wet! Holy crap!!!

I immediately removed both sets of car mats (the original carpet mats that came with the car, and the heavy-duty, super-thick, SUV mats my brother bought me as a 'car warming' gift, that I have over the originals) and then had Stud help me set up our elaborate drying system again.

I did Febreze the crap out of all the upholstery, so I hope that helps get rid of the foul odor. If it still smells tomorrow once it's dry, I plan to sprinkle a box of baking soda everywhere and then let that sit overnight before I vacuum it out.

When I first bought this car, there was a foul, icky smell going on, which I thought was in the vents. It did seem to improve a bit after I had an oil change done, and they switched out all the air filters. But, every once in a while, I'd get a whiff of something offensive. Again, it smelled a little like old milk. I'm basing this assessment on my memory of the smell in my old car after Stud dropped umpteen bottles of milk, not to mention a few sippy cups, which then dripped into the carpeting. Delightful, right?

Obviously, the car was detailed before I bought it. Now, I'm almost wondering if the carpet was still a bit damp when they put the floor mats back in it. The mats are rubber-backed, which would keep the carpet underneath from drying, right? Then, the day after I bought it, my brother brought over those heavy-duty mats and put them in for me. Is it possible that the carpet might not have ever fully dried? Seems a bit far-fetched, but any thing's possible, right?

If anyone has any other odor-removing suggestions, please pass them on. I vaguely remember reading somewhere that charcoal briquettes can be used to remove odor, so maybe I should place a few under the seats for a while. Leave me your tips, please!