Mice have a strong sense of smell, and certain scents can be repulsive to them. Here are a few smells that mice may dislike: Peppermint: The strong scent of peppermint oil or peppermint plants is often cited as a deterrent for mice. Ammonia: The pungent smell of ammonia can be unpleasant for mice. Mothballs: Mothballs contain naphthalene, which some people claim repels mice. However, use caution with mothballs as they can be toxic to humans and pets if ingested. Predatory urine: The scent of predators, such as cats or foxes, can make mice feel threatened and discourage them from staying in an area. It's worth noting that while these smells may be disliked by mice, they may not guarantee complete removal or prevention of mice from your car. It's best to combine smell deterrents with other preventive measures.