I remember I was really upset when I found out that they discontinued making those Bounce Dryer Bars, they were so absolutely perfect for under the hood and lasted so long. I had to clean out the nest every morning for the next 2 weeks until I found the info about strong scents keeping most animals away, and it worked the very first night, no sign of any nesting materials ever again after that.
You can also use strong scented soap, like Irish Spring, I used duct tape and taped them to the inside walls of my car for a few years. Fabric softener dryer sheets worked. But I was worried about something flammable under the hood too, and between the engine running and in direct sun, I didn't use the dryer sheets for long.
The peppermint oil now is the easiest and cheapest to redo for me. At least until they bring back the Bounce Dryer Bars!
I never did find out why they were discontinued.
