Car Talk Helps Bust the Myth That Soy Is Why Rodents Are Eating Your Car’s Wires

do you want to see what mice have done to my 4- runner? eaten wire coating, rubber, entire insullation under my hood, etc.

Just ran across this story and it gave me flashbacks of when I was stationed in Germany. Martens (like a ferret) eat EVERYTHING in or on your car and US cars seemed to be more susceptible than European cars. The speculation was that there was fish oil used in the mold-release products when making hoses and trim that European car makers stopped using many years earlier.

I remember turning down my street one night and seeing a marten standing on it's hind legs against a car side door and ripping the insulation off around the top of the window. Not long after I had chunks taken out around my Corvette windows. I also ended up with a ton of dog food and Milk Bones on the top of my engine, so it must have been a great place to relax.

I just had my Highlander’s wiring chewed up one afternoon on a college campus. Turns out, somebody else in same lot I was parked in had it happen as well two days prior. Turns out, we both had one thing in common: soy-based wiring. I don’t deny rodents will chew anything as you say but they are definitely attracted to the soy more so given a choice in a parking lot that parks around 60 cars. Perhaps the rodent would have chosen that morning to just hang out under the warm hood too and chew on other things but once he found the tasty soy wiring, it dug right in and it’s main focus was only the soy wiring.

I read about the so-called myth of rats & soy wiring. How do you feel about peppermint oil as a protection for cars, especially my Toyota camry Hybrid? 7609318813. David, California.

My insurance company believed mice ate my Audi wiring. I thing the teeth marks and droppings sealed the deal. Totaled the car. Audi’s response was “yeah, that happens all the time”.

Not a myth. Had two cars that were parked side by side. The newer Toyota, they chewed $800 worth. The Subaru which was a 1998, two years before soy-based wiring started being used was untouched. Just a week ago had our 2016 Honda Civic wired chewed at $250 worth. Honestly, I think you're getting a kickback from some auto maker to write this bogus article!

Soy based wiring IS the problem. I have a 2003 Ford truck and a 2008 Mazda that are parked outside in my driveway as the rule all year long. I have found mouse droppings in both engine compartments. Aside from some insulation that has been a bit shredded (for nesting material) nothing else has been damaged. I have a 2019 Toyota Camry that is parked in the garage year round. Last week I could not park the Camry in the garage for a few days, so it stayed out in the driveway with the other 2 vehicle. Mysteriously the AC in the Camry stopped blowing cold air last week. An appt. at the dealership resulted in a diagnosis of "rodent chewed wires" and a repair cost of $8000 to replace the entire harness. I jokingly asked the service tech if Toyota was using cheese flavored wires and he said no, but they do use soy-based coating. This is absolutely caused by the enticing flavored wire insulation Toyota uses. For anyone to say otherwise shows a lack of ability to get to the truth.

My 2020 RAV 4 had over $ 7000. of repair from mice .......found dead ones in glove compartment.....insurance agent stated that Toyota's are a common claim..........Toyota service admits to soy theory and the commonality

My 21 Highlander with 10,000 miles on it it is in for this problem right now. In 45 years I have never had a critter in my garage. My service manager told me the coating on the wiring on Toyotas attracks the rodents. So you may not believe it but apparently Toyota does believe it. Not covered under warranty though, of course.

Just got our 2023 4runner back from Toyota. Rat chewed through the wiring harness, not covered by warranty, had to file an insurance claim. We have never had a rodent problem and have 3 other vehicles(08′ toyota tacoma, 97′ jeep xj, 73′ chevy truck + my 09′ ford escape that we traded in) parked at our house and have lived here 5 years. I was in complete disbelief that a rat(s) could have gotten into my brand new vehicle and caused $3000 worth of damage in a month and a half, until I started researching online.
We argued with the dealership saying how could a rat chose the brand-new vehicle and leave the other vehicles alone, their answer…”it has been colder the past month and rodents will look for somewhere warm to sleep”
But now after reading everything I have read online I know they are not going to admit that it’s a problem with the coating they use on the wires, because then they would probably have to cover it under their warranty.

Maybe it isn't the soy, but I had a 2010 Prius that was loaded with mice all the time, no matter what I tried. Some solutions would last for a while, but the mice always eventually came back to all or part of the car. Got rid of it and got a 2016 Honda CRV. No mice - ever. Same storage location, still plenty of mice around. But none in my car. I even left food in the car, and they still didn't come around. Tons of people on the net complaining about this problem with the Prius. So maybe it wasn't the soy -- I mean, if Ray says so, I'm inclined to believe him. But there is something about the Prius. So, in conclusion ... poor research and bad article.

TOYOTA is a common theme. But they got the lawsuit dismissed. Nice. Poor Toyota really needs the money. I had two Toyotas and loved them for everything but the mouse problem, but I'll never buy another Toyota. Mice were in the engine area, the glove box, inside the seats, in headliner, etc. etc. Insurmountable.

I have had 4 Mazda 3s and this is the first time I had this issue. I had my last Mazda 3 which was 10 years old parked in the same spot and did not have a problem. It is definitely an issue with the new cars.

Just spent $1000 at the dealer when my #2 soy coated injector harness was chewed through by this debunked problem.

So, this was a few years ago, and doesn’t really belong in this thread, anyway, except that it deals with rodents chewing automotive parts… Anyway, my ex had a squirrel break into her apt. one afternoon, & steal a piece of chocolate; she chased it off, but on her way to the school where she teaches Norwegian the next day, she said she smelled gas when she got to her car, but she assumed it was another car, & left for work. She said the smell only got worse while she was driving, and she watched the gas gauge go down, “really fast!” When she got to her destination, she checked under the hood, and found a gas line has been chewed nearly through! She’d had to replace it before she could go anywhere… Bad experience all around…

I thought the soy explanation was a bit far-fetched, but I'm having a little trouble explaining what goes on in my driveway. I have six cars sitting out there, and there have been others over the years. They all get some rodent activity. But ONLY the newer ones WITH soy wiring have had trouble with wiring chewed through. It has happened over and over again to the same cars, while the others have had no problems. I'm about to make non-soy wiring insulation a buying criterion. I notice that Ray said that it may one day be shown that it is a problem, only that there isn't any evidence yet. I'm open to other explanations, but the article's "It happens to all cars" attitude won't begin to account for my experience.

2023 Genesis 2,500 miles . Wiring harness destroyed , plastic cowling below wipers completely destroyed . Have been waiting for over three months for a new wiring harness. Have spent over $3,000 on rental car. Insurance would only pay for 30 days of rental on a comprehensive policy .Was told by dealership service writer to get rid of the car after it’s repaired. We plan to take the service writers suggestion. Love the car but not worth going through again .

Rats chewed the wiring harness on my Dodge Charger twice! The Equinox sitting right next to it had no damage. If it's not true why did Honda create and is selling rat deterring tape to wrap the wires. They had to use the tape on my car. Just Google Honda rat deterrent tape.

Hmmm so I’ve had cars and trucks almost fifty years and never had a problem with rodents chewing through my electrical until I got a late model Lexus. One would think manufacturers would make a greater effort to solve this problem. I finally got rid of the Lexus.

ugh! currently sitting without my 2019 Toyota CHR for the SECOND TIME i n 10.5 months (May 2022 / April 2023). Last year $15000 worth of rodent damage. Yesterday woke up to all my dash lights on and FIVE warning messages across my screen. Drove to Toyota and left my car in their service parking lot prior to opening. I've had enough. They call just before closing and stated that a rodent chewed through my ABS wiring, my Airbag wiring and my Emergency break wiring and that the tech wasnt done inspecting the car for more damage. Toyota didnt even bother to call me at all today, the day before a stat holiday to provide an update on my car. So here I am long weekend, with no car.
Last year Insurance paid for the repairs, $15000, called them again they pretty much laughed and said that if I put through another claim, for the same problem in less than a year, the company may or may not pay for it again, but that they will drop me as a client at my end of year review and that I will then be flagged by high risk and no decent company will take me on, so any company that will cover me will have high premiums :( Parked in the same driveway is a Nissan (2015) Rouge and not a single sign of a rodent ever! used to park my Toyota Rav4 (2016) and my Toyota Matrix (2006) again no problems at all.
Sadly I will need to move away from Toyota vehicles, as I cant risk this anymore.

I'm inclined to believe it's the type of wiring and/or the design of the car (easy access for rodents). Just happened to us again this morning - 4th time! We had a Chev Tahoe and an Acura MDX parked in our driveway for 20 yrs. Never had a wire chewed. We now have two porsches (2017 & 2019) - same driveway. Each have been chewed twice. Maddening and expensive.

I'm inclined to believe it's the type of wiring and/or the design of the car (easy access for rodents). Just happened to us again this morning - 4th time! We had a Chev Tahoe and an Acura MDX parked in our driveway for 20 yrs. Never had a wire chewed. We now have two porsches (2017 & 2019) - same driveway. Each have been chewed twice. Maddening and expensive.