I’ve use a product in the pas called Skunk Kleen to remove skunk smell. I’ve used in in the house on the window screens and on fabrics too. I was surprised how well it worked. I think it’s something you can buy at a pet store
Hydrogen peroxide is cheap, and works about as well as anything. It’s also easy to find.
There are some additional suggestions on the Wildlife and Your Car page (http://www.cartalk.com/content/features/wildlife/index.html).
Dr Kieran, Car Talk Animal-Vehicle Biologist and Wildlife Guru
I had a friend who nailed a skunk one night and after repeated washings it still stank. Finally getting under the car he found that most of the skunk was wedged inside a coil on his coil-over-springs rear suspension. What laws of physics allowed for this we never figured out, but he said that it sounded like a bowling ball being dribbled under his car. He had to use power hedge trimmers to cut the carcass into small enough pieces to remove it. But a few days later it was still stinking to high-heaven. It wasn’t as bad, but is there good skunk stink?
Getting back under the car he found that there were still small pieces of skunk wedged into various crannies in the undercarriage, and that he believed that the scent gland had been one of these parts.
Get the car to a place with a lift and have them powerwash the entire undercarriage. She might have to spring for some goggles and Tyvek suits for the poor guys that have to risk dead skunk parts and stink getting on them.
Removing Skunk Smell
A friend tried it once . . .
. . . You want to see a ticked off skunk ?