Unless you're taking a pet for a ride, you don't want any animals exploring your vehicle. Unfortunately, the nooks and crannies in a vehicle can prove especially appealing to mice.

The problems related to mice in cars go beyond the basic annoyance of having a rodent crawling around a vehicle's cabin. The Hastings Natural History Reservation, a biological research station of the University of California, says mice can gnaw on wiring, insulation, and other vehicle components. This damage can lead to some major repair bills, especially if the mouse has crawled into an area of the vehicle which is hard to access.

Eric Evarts, writing for Consumer Reports, says problems with mice may be more common as automakers start to use biodegradable materials in vehicle parts. Rodents are much more likely to gnaw on plant-based materials, such as soy protein door seals or fungus-based bumper foam, than they are to chew on metal or plastic parts.

Even though the tires elevate a vehicle off the ground, some mice are excellent climbers and can make their way into the cabin or under the hood. Mice are most likely to get into vehicles that are stored for long periods of time, though they can also affect vehicles that are driven regularly. A warm engine can prove especially appealing when the days start to get cooler.

Several different deterrents have been suggested for keeping mice out of a vehicle. Their effectiveness is likely to vary, depending on the tastes and cleverness of mice in different areas.

One option is to create a displeasing odor that will discourage a mouse from getting into the vehicle. The Hagerty Insurance Agency, a classic car insurer based in Traverse City, Michigan, says mothballs, sulfur pellets, or predator scents can drive mice away. These odors won't appeal to the driver either, but they can easily be vented when you take the car for a spin.

Dryer sheets or scented soap are more aromatic alternatives. Placing these items around the vehicle, as well as in the cabin and under the hood, can help keep mice at bay, though some rodents may not be discouraged.

Ultrasonic devices are available for the express purpose of letting mice know that they are not welcome in your car. This item draws a small amount of power from the vehicle's battery to produce an extremely high frequency tone which will be unpleasant to any visiting rodents.

Evarts says specialized rodent tape can protect wiring and other vulnerable parts of your vehicle from damage. This item is similar to electrical tape, but it is treated with capsaicin – the molecule which produces the spiciness in chili peppers. This ingredient will quickly teach a lesson to any mice who try to nibble on it.

Traps can be an especially effective choice when placed around the vehicle or inside the cabin. You'll have to check them regularly to remove dead mice, replace bait if it has not triggered the trap, or remove and release mice if you are using a live trap. The Hastings Natural History Reservation says that while live traps are humane, it is also possible that a captured mouse will soon return to its preferred nesting area even if it is released far away.

Poison can also eradicate any rodents who are attracted to your vehicle, though you should be careful in its application. This material can be harmful to pets or other animals if it is left out in the open. If poison is set inside the vehicle, a mouse may crawl into the vents or another inaccessible area before it dies. The dead mouse will give off a horrible smell, and it might cost you a lot of money to remove it.

Combining multiple methods may improve your chances at success. For example, you could set out traps while also placing dryer sheets in and around the vehicle.

Some methods aim to make access to your vehicle more difficult. Steel wool or wire mesh can be placed in the pipes and over any other openings. Closing the air vents can keep mice from making their way into the cabin. You can also elevate a stored vehicle on jacks to make it harder for mice to access.

The Hastings Natural History Reservation says stored cars can be protected through a "mouse moat," which puts up a defensive perimeter around a vehicle. Aluminum flashing clipped to a wooden corral presents a barrier against climbing mice, and it can be removed rather easily when you need to move the vehicle.

You may want to put some protective material on top of the flashing to prevent injury on the sharp edges. Some options include vinyl or a section of rubber garden hose.