To keep away martens from the engine compartment of cars (the ones living in urban environments like to crawl in there when it gets colder, and then nibble on t

To keep away martens from the engine compartment of cars (the ones living in urban environments like to crawl in there when it gets colder, and then nibble on the wires), we (= Dutchies) hang a bathroom refreshener under the hood. You know the plastic ones with the rock-like thingy in it that smell very strong. You have to replace them pretty regularly though.