It worked on my daughters car. She lived in a woodsy area, that had a community garbage dumpster nearby, and rats kept chewing her car wiring. After installing it we had no issues.

Except the odd young person complaining about the noise the car kept making… That I couldn’t hear at all.

Under the hood? If it is hot out maybe spray the hose in there. It might come back. Amazon sells a device that perioeically makes high pitched noises above most human hearing range, you install it onto the battery terminals and zip tie it somewhere

If you don’t mind soaking them, a sink of warm water and a few teaspoons of LAs totally Awesome cleaner from certain dollar stores or home depot, will clean off almost any dirt, oil, grease, stain etc. You can give them a pre spray too before soaking.