How To Keep Mice Out Of Your Car Engine Compartment

Rodent Guide
Written By Rodent Guide

I believe in treating all creatures with respect. My mission is to ensure everyone understands how to protect their home from rodents without using cruel methods.

Getting mice in your engine could be costly.

Firstly, you have the cost of the repair. Secondly, you may drive a car with unknown damage. That could result in an accident.

You need to get rid of them ASAP to stop them from coming back! After all, a car in one of the places mice like to nest outside.

Here is my guide for dealing with mice in your engine compartment.

How To Keep Mice Out Of Your Car Engine Compartment

How do mice enter your car?

Before contemplating how to keep mice out of your car engine compartment, you need to find out how they gain access to your car.

While your car might look protected after locking it, mice have several ways of gaining access to your car. Because of their size, it is easier for them to squeeze themselves through little openings.

In most situations, they crawl into your car engine from under the car and make their way to different compartments in your engine.

Here are a few entry points that a mouse can use to gain access to your vehicle.

  • Pedal shafts
  • Vents
  • Steering columns
  • Holes around cables

Besides these, mice can enter your car compartment if you have a broken or cracked window. Therefore, it is vital to keep your car unattractive and inaccessible to these little creatures.

Signs that indicate you have mice in your car

chewed wires

If you have a car, here are a few signs that will tell you that you are under a mice attack.

Once you notice at least two of these signs, it is time to swing into action; else, they will probably make a mess of your car.

Unpleasant Smell

If you have an air freshener in your car but still experience an unpleasant smell, it is a pointer that you are under mice attack.

While you might not see the mice, the presence of a bad odor is a sign that signifies their presence.


Hardly can mice stay in a car and not chew or make scratching noises.

These noises will often be scratching your car engine surface or biting wires in your engine compartment.

Once you notice an unfamiliar sound in your car, you have a visitor in your car to deal with.

Chew marks

While this might not be common in new cars, there is the possibility of seeing chewing marks in an old car.

Therefore, check for chew marks on the seat belt, cushion, floor mat, etc.

Mice chew everything!

Faulty Display

When mentioning chew marks, mice can chew wires connected to your display unit.

This can affect the unit and lead to a faulty display on your car dashboard.

What can mice do to your car?

car engine

Once these creatures gain access to your car through the aforementioned means, they create havoc that might cost you.

Firstly, they can cause foul smells in your car, which leave your interiors unhygienic. Furthermore, they chew your cables, which will require replacement.

In addition, the wiring system can get faulty because of chewing, which can result in accidents and affect other parts of your car.

Regrettably, once they build a nest for themselves and multiply, they pose a bigger problem that makes it hard for you to drive the car.

Therefore, you need to find a feasible solution to deal with these mice before they wreak havoc that will cause you to break the bank.

How to keep mice out of car engine compartment

mice on glove

Dealing with mice isn’t something to take lightly because of the danger they pose to your car.

Nevertheless, you can use the following proven ways to keep mice out of your car. Importantly, you have to select the best option that suits your environment, resources, and vehicle.

Furthermore, you can combine these methods to keep mice out of the car engine compartment to get a better result.

1. Park your car in a garage

If your home has a garage, you should use it.

Indeed, mice can also get access to your garage, but if you seal up any entry points and keep them tidy, the chances are slim.

By keeping the car in your garage, you reduce the chances of getting into the engine compartment.

2. Honk them away

Although not the best option, you can scare them away by honking your horn.

If your car key fob has that function, you can do that from a far distance.

Loud noises tend to scare mice away as they love to hang around a quiet environment.

Nevertheless, you don’t have to go overboard and upset your neighbors while honking your car.

Before starting your car, wait for some seconds after horning. However, this might not permanently chase the mice away as they will eventually return after the environment is calm again.

Therefore, you can not really rely on this one method to deal with mice in your car engine.

3. Use Mouse deterrents

mouse trap

You have several chemical and physical options to deter mice from entering your car engine compartment.

Depending on your environment, resource, and car, you can combine the following mice deterrents:

Scent repellents

You can use cayenne pepper, peppermint oil, or cedarwood around your car.

Naturally, mice avoid these scents, and those are a more humane option compared to using poisons.

However, avoid placing these scent repellents close to your windshield washer area; else, the smell will infiltrate the car’s interior.

Electronic repellent

You can use electronic repellent to deter mice from your car.

The electronic repellent is a cordless device you can place inside your car, which emits a tone whenever it hurts mice.

However, it is inaudible to humans when in use; you have to check if it has caught any mice once in a while.

They can be quite effective in dealing with mice in your car.

4. Mouse Traps

Another option is to use mouse traps, which can keep mice away from your car engine.

Once you notice the entry point, you can place them close to this area and wait for the mice to get trapped.

These mouse traps are of various types, including snap traps and live traps.

I recommend a multi-catch mouse trap, because you can leave it for a couple of days.

5. Clean your surrounding

Most times, mice find your car as a breeding ground if your environment is not clean.

Therefore, find any potential hiding place and keep the place clean. Furthermore, avoid parking your car close to a supermarket or a garbage can.

Overall, clean your surroundings and never allow mice to build a nest for themselves.

Keeping a hygienic, litter-free, and non-cluttered environment will save you a lot of trouble in the future.

No Food Zone

While cleaning your environment helps a lot, avoid leaving food items in your car.

Rats and mice are living creatures and must find food for them to survive. Therefore, when you leave food items or particles in your car, you attract these rodents into your vehicle.

To restrict their movement into your car, ensure your children don’t drop any food crumbs while eating. Therefore, make sure you do not eat in the car.

What next after using mice deterrent

Where Do Mice Nest In A House nest example 3

In most situations, the mice will die in your car, which means you need to do some cleaning. Do not vacuum the vehicle immediately.

Remember, mice urine and dropping can cause Hantavirus when you breathe it.

Therefore, first, take your car to an open area to air it out.

Get cleaning items with rubber gloves to protect yourself.

Mix water with household bleach to spray the affected areas. Allow it to stay for five minutes before wiping the area with a paper towel.

Furthermore, use a sponge with the bleach solution to scrub the area.

Finally, trash the items you use in a plastic bag while washing your hands using soap after removing the gloves.


Having a mouse in your engine spells danger! It could cost a lot of money to fix, and it could cost a lot more if they chew through something and the car becomes faulty.

You should pop the hood every once in a while and check the engine bay for signs. Whilst you have it open, please give it a clean. A clean engine bay will reduce the chances of an infestation.

Good luck!


About the Rodent Guide

I’m an expert in do-it-yourself rodent control. For more than 20 years, I’ve dedicated my life to helping people live harmoniously alongside these critters by sharing rodent control solutions that are effective and kind.

I believe in treating all creatures with respect. My mission is to ensure everyone understands how to protect their home from rodents without using cruel methods.

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