My '07 Accord always sits out (husband's car goes in garage) and if it's been raining and or snowing (damp weather) I notice that on my way to work in the morning, when I go to get the car up to 55 mph I'll get this burning or odd smell. One morning I thought you might be able to compare it to moth *****. Could it be the spark plugs? It's been happening for quite a while. But I also know some kind of transmission recall on the '07.

 

oil leaking from valve cover onto exhaust most likely.

Look at the valve cover and see if you see any leaks.