There was once a little mouse that caused a big problem.
The critter crawled up in the wheel well of a parked car, made his way over the brakes and up into the engine. Most rodents would stop there; it’s a nice nesting spot. But this fella had other plans.
He kept going until he was inside the dashboard and couldn’t get out. There, he died (I didn’t say it would be a happy story). The rancid and revolting odor compelled the car owner to bring it to Avis Ford in Southfield, Mich., where service technicians made the unsavory discovery.
“Usually you find a wiring harness for the engine or the fuel injection system that is all chewed up,” said Avis Ford’s Service Manager Larry Sirgany. “We’ll find a car that’s been sitting for a couple weeks and it will have a big nasty nest in there, too.”
Over the years, Sirgany has found plenty of flora and fauna in car engines. There are grass and twig nests and dead — or sometimes alive — vermin and lots of chewed wires. The resulting damage is costly to fix.
But this spring, amid the stay home order during the coronavirus pandemic, the rodent ruination to engine has been exceptionally high in some places.
“I’ve seen a solid dozen to 15 cars with damage in the last six weeks,” Sirgany said. “Typically, I would have two per month this time of year.”
Hundreds in repairs
In fact, an April 30 report in The New York Times said a dealership out East had five people call in one week to complain of rats living in their car engine. One couple got an alert of engines trouble while driving and remembered seeing a rat scurry across their driveway as they left. So the couple returned home, opened the hood and found animal feces and urine all over the engine, as well as sticks, leaves and small bones.
An employee at the couple’s service center said such incidents have become “all of a sudden super common” within “the past two or three weeks,” the Times reported.
Last month, the Centers for Disease Control and Prevention warned of unusual or aggressive rat behavior caused, in part, by many restaurants shutting down during the pandemic. Rodents depend a lot on tossed out food scraps from restaurants.
Now the varmints are searching elsewhere for food and your engine could be it. Some car brands, such as Toyota, use soy-coated wiring, which can be a delicious treat to a rodent.
Also, in cold weather, a car is a source of heat for mice, rats, squirrels, woodchucks and opossums. That’s usually the time of year when Sirgany sees the most engine damage. The creatures crawl in the engine to keep warm and chew on the car’s wiring while in there, wreaking havoc on the electrical system.
“Typically, they can get fairly time consuming to do a repair — at least two-to-four hours putting it all back together,” Sirgany said. “So it’s a $400 to $600 repair.”
The cost typically does not exceed a person’s deductible, so it’s usually an out-ofpocket expense, he said.
There is also a possible danger. If a mouse makes a grass nest, typically the size of a baseball or a golf ball, it could potentially start a fire, some experts warn.
‘Staring right at me’
The good news is usually by the time spring rolls around, rodents stay away from cars because there’s more activity with people outdoors.
“This year, with COVID, that’s not the case,” Sirgany said. “The cars have been so quiet, they’re parked, they don’t smell like people and they become pretty attractive to a rodent.”
Most customers will be alerted to an issue from a warning light signaling an engine problem. The rodent’s damage will interrupt the car’s wiring system, but it does not usually paralyze the car, Sirgany said.
The customer will bring the car to the dealer and that’s when Sirgany’s team opens the hood to diagnose the problem. He will usually find the clues, maybe twigs or leaves, sometimes followed by a surprise.
“Every now and then you find the critter still living in the car,” Sirgany said. “The last one was four years ago. It was a woodchuck staring right at me and he wasn’t even interested in leaving.”
Sirgany gently shut the hood and called wildlife experts to safely remove the woodchuck, also called a groundhog.
Polish the pearly whites
But even in those vehicles that use petroleum-based wiring, cars attract rodents simply because they are dark, provide shelter and offer the chance for dental hygiene, said a rat expert at University of Michigan.
“All rodents have these ever-growing teeth and they need to chew on things to keep them from getting long,” said Ben Dantzer, professor of psychology at the University of Michigan. He studies mice, squirrels and rats to learn how they make decisions.
In his years of studying rodents captured from the wild, Dantzer is certain of one thing: They have great smiles.
“Never once, do you find a wild squirrel that has teeth that are screwed up,” Dantzer said. “But rats used in biomedical research, their teeth are long and out of control because they haven’t had anything hard to chew on.”
In the wild, rodents consistently chew on rocks and trees to keep their teeth worn down and sharp, Dantzer said. If they did not do that, they could die from overgrown teeth locking their jaws.
“So underneath the hood of a car, it’s a nice place to sleep and you’ve got all these wires around. You need to chew and grind your teeth down so you chew on those,” Dantzer said. “Then, it ends up shorting out the car’s wiring.”
He is not surprised at an increase of rodents nesting in car engines during the pandemic.
“It’s not a situation where we have this burgeoning population of squirrels and rats,” Dantzer said. “It’s a crime of opportunity. You have all these stationary vehicles.”
Dogs, cats and talk radio
Now that you know everything you ever (or never) wanted to know about the rodent lifestyle, there are many ways to pest-proof your car.
The most obvious is to drive it daily, because unlike our mouse or Sirgany’s woodchuck, most rodents will jump out of the engine and not return once the car is regularly in motion.
Also, leaving it outside makes it less appealing.
“If I’m a squirrel or a chipmunk and the car is out in the sun, it’s a less attractive object because the garage is dark and protected,”
Dantzer said. “I might park my car in the driveway because it’s lighter, in the open and there are dogs being walked all around.”
Here are some other suggestions from the experts:
- Spray commercially approved rodent repellent around the lower perimeter of the vehicle and wheel wells.
- Peppermint oil sprayed around the car works too.
- Some automakers make a tape with chili oil on it. It wraps around wiring and has a repelling taste to rodents.
- Keep bird feeders far away because, “Bird feeders aren’t just feeding birds; they’re feeding rats,” Dantzer said.
- There are moving fake owls or scarecrows that will scare away rodents.
- Look at the car daily, open the door and the hood, shine lights on the engine.
- Cats and dogs are predators, so you can leave them in the garage for awhile, if the temperature is safe for them.
- Set traps near the front wheel well where rodents enter.
It also helps to think like a rodent. Sirgany keeps a classic car in storage and has a radio on at all times.
“The noise seems to work very well,” Sirgany said. “I keep it on talk radio so, from a rodent’s point of view, there’s always a human there.”
If you do happen to open the hood and see a rodent, don’t flash back to the 1971 cult horror movie Willard. They are not going to swarm and eat you alive.
“They’re not going to jump on you; they’re not going to attack you,” Dantzer said. “But if squirrels ever figured out that we were as afraid of them as they are of us, they could inflict some serious damage.”