Back to the question about the smell..

I had this problem once.. and looked everywhere until I finally put the car on a lift and used a good light. This may not be the same problem you have but for what it's worth..... It turns out that a plastic bag somehow got stuck on the back of my muffler and some part was burned and 'glued' to the muffler. Whenever the car is hot.. the muffler would 'roast' that layer of plastic bag that was stuck on it... It drove me nuts for days before I discovered it. I suspected EVERYTHING!!!!