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Your engine has various components, but rats shouldn’t be one of them. If you suspect you have rats in your engine, here are some steps to help you eliminate them.

How Can I Determine If I Have Rats in My Engine?

Rat Droppings

The smell of rat droppings can’t be mistaken for anything else. Rat droppings have a musty odor that smells like rotting cheese.

If you can smell the droppings, you will most likely be able to identify them as well visually. Finding rat droppings around your car’s battery casing is common.

Scratching Noises

If you hear scratching noises coming from your dashboard, your car isn’t possessed. It’s probably a rat. If you hear something moving around, such as metal objects, that’s a different issue. Mechanisms that are moving around in your car could be due to an air conditioning malfunction and various other things. If you hear scratching noises that sound like little nails, there’s a good chance you’re hearing the movements of a rat.

Chewing Marks

Although chewing marks on the inside of your car are uncommon, it’s not impossible. Rodents will happily live on the inside of your car because there are different places where they can make a nest and tons of other objects to chew.

Illuminated Check Engine Lights

Your check lights can appear because of rats chewing on the wires of your vehicle’s harness. The excessive chewing on these wires can cause your vehicle’s sensors to malfunction. These malfunctions, especially check lights that light up red, indicate you have a serious issue that needs to be addressed by a mechanic. Some of the damage that can occur can make your car difficult to drive or not drivable.

Windshield Wiper Fluid

Rat may have chewed on your windshield wiper hoses if you experience a sudden loss in pressure with your windshield wiper fluid.

Why Do Rats Enter Car Engines?

Rats are tempted to enter car engines because it’s the ideal location for nesting. Rodents, including mice and rats, are always on the prowl to find the best place to nest, and engines provide an excellent location because they are warm and dark, allowing them to hide until you turn on the engine, maybe. Your car’s engine has multiple parts that are not metal, allowing rodents to chew through them and use them as insulation easily.

What Damage Can Rats Do to Engines?

Rats can climb on your car tires and onto the front wheel wells, which gives them access to your engine. Once these rodents are inside the engine, they can build their nest, store food, and birth their offspring. The most severe damage rodents can cause engines is chewing through the non-metal components. Your car has tons of different wires, and they don’t mind chewing through every single one. System malfunctions can also occur because of rodents using your car’s wires as a chew toy, making your vehicle more susceptible to fires.

Can Rats Get into the Cabin from the Engine?

Yes. It doesn’t take much for a rat to enter other parts of your car, such as the cabin, once they get into the engine. There are also other points of entry rats can use to enter your car, including the steering column, pedal shafts, the holes around cables, and the vents. Rats can easily maneuver in and out of tight spaces because they are flexible, which allows them to fit their bodies into almost any space.

How Do I Get Rid of Rats in My Car’s Engine?

Getting rid of rats in your car’s engine isn’t as difficult as you may think.

Clean the Surrounding Areas

Clean the areas surrounding your car. Ensure there is no garbage or other debris around your car, in your yard, or on the sidewalk. Garbage is a food source for rats, so if they find one piece of food, they will continue to wander to find more food.

Walk Around the Car with Your Pet

Rats aren’t fond of the smell of your pets, so walk around your car and nearby areas with your cat or dog and let them rub their scent on everything.

Use Traps & Repellents

You can also place a trap or two under the hood of your car and beneath your car to catch rats if you’re okay with using this method. Amazon has rat repellents and traps.

What Do Rats Hate the Most?

Another way you can rid yourself of being in the company of rats is by using their dislikes against them.

The Smell of Danger

Rats hate the smell of predators because it sends their senses into overdrive. The scent of certain predators such as raccoons, cats, ferrets, and similar animals, will keep rats away.


Rats can’t tolerate the strong smell of peppermint. You can use peppermint oil around and in your car to prevent rats from entering your car.


When you hear the word citronella, you may think of candles and mosquitos, and you’re right, but it also wards off rats. Apply citronella to multiple places on and around your car to make rats think twice about nesting there.

What Is the Best Rat Repellent for Cars?

You have options for rat repellent for your car. The trick is finding a repellent you can deal with, such as peppermint, mint, or eucalyptus oil. Don’t mix these oils with anything else, including water. Use a medicine dropper to put the oil in different locations in and around your car. You can also use under-the-hood rat repellent if you can’t stand the strong smell of the oils.

What Home Remedies Can I Use to Keep Rats Out of My Car?

Popular home remedies to keep rats out of your car include peppermint oil and other essential oils. Rats can’t tolerate the smell of these oils because they have a strong aroma, making them run in the other direction. You can also use cayenne pepper.

Don’t wait until you have a family of rats making a home in your car or using your car’s parts for chew toys. If rats are giving you trouble, these remedies will help you get rid of them.