I walked in high winds and lots of rain on November 11th and my boots leaked. I wasn't able to sort my car out until a week later. I began to notice a sweet sickly smell that just wouldn't go away, a bit like having a dead rat in the car!
I sorted my car out and put everything away in its right place, in the garage and in the wardrobe. Over the next few days the smell persisted.
I decided to really have a detailed look and then realised it was coming from my Sorbothane boot inserts. Although I had taken everything else out, including my boots, I had taken the Sorbothanes out to dry them and had left them in the car. I put them to my nose and went Ughhh!
I took them out of my car and just left them on top of our wheelie bin to air! Problem solved! My car smells normal again!