When cold weather moves in, your car or truck can quickly become the new hot spot for uninvited guests. Mice and rats are looking for shelter, squirrels want to stash their supplies, and the neighborhood stray cat has decided to use your engine bay as a heated blanket. None of these moochers helps make the car payment, though.

While cats seeking warmth need a safe exit, rodents can leave behind nests, droppings, and chewed wiring. A little prevention can help discourage unwanted guests, and knowing how to inspect your vehicle can help you catch trouble before it becomes a repair bill.

Here are five ways to make your car less inviting this cold season.

Remove Food Sources That Attract Mice and Rats to Your Car

The seat snacks that pile up in hard-to-reach places might have outlasted the last three presidential administrations, but to a rodent, they’re dinner. That includes condiment packets and sugary residue. Remember that soda spill lingering in your cup holders? 

Remove food wrappers, crumbs, and forgotten snacks from the interior and trunk. Then look beyond the car and where you typically park. Accessible pet food, birdseed, and garbage near your parking spot can help keep rodents close by. Store food in secure containers and keep your trash can lid closed.

If cleaning requires removing interior trim, check the vehicle’s repair procedures first. ALLDATAdiy provides manufacturer repair information and illustrations to help you follow the correct removal and installation steps. Remember, manufacturers love to hide fasteners behind interior trim, and seat mounting bolts have specific torque requirements. Consult the applicable procedures and specifications in your ALLDATAdiy subscription before taking things apart.

Keep Rodents Away From Your Garage and Parking Area

Beyond removing food sources, keeping your driveway clear of leaf piles that provide shelter can help deter these terroristic tourists from your vehicle. A quiet car parked beside a pile of leaves gives rodents a convenient place to house hunt without the watchful eyes of birds of prey and cats.

If you park in a garage, address gaps around doors and other building openings. A garage offers better control over the surroundings, but rodents have an incredible ability to squeeze through small openings. A gap beneath the garage door might as well be an open invitation.

Even with the hood and doors closed, rarely used vehicles deserve extra attention. Check them regularly for signs of returning rodents, especially around the engine bay and air intake areas. Nesting material or unusual blower noises may also warrant inspecting the cabin air filter and blower housing using your vehicle’s service procedures.

Check for Cats and Rodents Under the Hood

Before your first cold morning start, tap firmly on the hood, check around the tires and wheel wells, and sound the horn to encourage hiding cats to leave. If you suspect an animal is inside, open the hood and confirm it has cleared the vehicle before turning the key. A warning knock doesn’t equal an eviction notice in a rodent’s mind.

With the engine off and cool, look for nesting material, droppings, or visible damage. Pay particular attention to air intakes, filters, coil pack and injector wiring, especially if the vehicle has been sitting.

Need to access an air filter housing or remove a cover for a closer look? Log in to ALLDATAdiy and search for “air filter” to find the applicable manufacturer procedure before reaching for the tools.

Choose Rodent Repellents for Your Car’s Engine Bay

The internet has no shortage of pest prevention advice. Unfortunately, “someone in the comments swears by it” is a low testing standard.

Peppermint-based rodent sprays are one option worth considering. They may temporarily discourage mice and rats, but they aren’t an invisible force field. Scent-based sprays wear off and may need regular reapplication, especially after exposure to water.

Choose a repellent specifically labeled for rodents and the location you plan to treat. If you’re using it under the hood, the directions should explicitly allow that use. Follow the instructions for application, placement, and reapplication rather than spraying the entire engine bay and hoping for the best.

Also, “natural” doesn’t automatically mean safe for animals. Concentrated essential oils can harm pets, so avoid homemade peppermint-oil treatments where cats or dogs could contact or ingest them. Rat poison can also harm other animals that eat poisoned rodents. After all, protecting your car from rats shouldn’t put the neighborhood cat at risk.

Inspect and Repair Rodent Damage to Car Wiring

Finding a nest, droppings, or chewed wiring means it’s time to inspect, not turn the key and hope for the best. Before cleaning, follow CDC vehicle cleanup guidance, including battery precautions: ventilate the vehicle for 20 minutes, wear protective gloves, and wet contaminated material with an appropriate disinfectant for the recommended contact time before removing it. Don’t sweep or vacuum dry droppings, and get professional help for extensive contamination or areas you can’t safely reach.

Once cleanup is complete, inspect for damage and address it before driving. If rodents have turned your wiring into a snack, ALLDATAdiy’s interactive color wiring diagrams and diagnostic procedures can help you trace the affected circuit and follow the manufacturer’s repair instructions. If accessing the damage requires removing covers or panels, check those procedures first, too. 

Keep Animals Out and Your Car Ready for Winter

Winter is already hard enough without adding rodent damage or an injured kitten to the list. These tips can help you hang a “No Vacancy” sign at the varmint suites. And when inspection or repair takes you beyond opening the hood, ALLDATAdiy gives you vehicle-specific repair information to help tackle the next step with confidence.

Because your car should be ready for your next drive, not someone else’s winter lease.