I live in a forested area and have been dealing with rodents in the cars since moving here- about 20years ago.
Rodents are either mice, pack rats (specifically mexican wood rats), squirrels, and rabbits. 2 Cars- used rather frequently but can sit for maybe a couple of weeks without use. They have built nests on top of the intake valve head, under the designer valve cover (which covers the valve cover and spark plugs, the inside fan housing and beyond, in the trunk, on top of the lower splash pan cover and other misc spots.
The sequences of attempted remedies: I have a carport.
-Installing lights above open hoods and under the cars. Did not deter but I still do the task.
- Used items called "cabs"- which are natural substances in a small burlap bag that are "designed to repel critters". Need to
be replaced after 3 months. In the engine compartment and cabin and trunk. Not effective.
- Moth balls in pouches. Not effective
- Shaved Irish Soap bars on ground around car exteriors. No use but smelled great.
- Peppermint oil in many engine compartment area including splash panel.- Nope
-Snap traps around the tires and key places in the cars. These did not appear to work but I stopped using them when I
found a bird in one.
After all these tries, I just sort of just kept checking things often and removed nests, sometimes dead mice smells were the
clues to hard to see places.
I bought a new Mazda 6 in 2016 and brought it home. Had if for a couple of days but neglected to open the hood (a sometimes occurrence but not often) and the next day tried to start it and it ran very rough. Sure enough some critter(think a mouse) chewed the spark plug harness wiring. Brand new car, brand new $600 repair ( not a warranty item of course).
Now this has been a long reply but I want to get to what seems to be the most robust solution to this problem.
The learning for the new cars is that the Japanese cars use predominately a soy-based plastic for their wiring. Some other car types too. They have made available rodent repellent wire wraps. I have done this on the Mazda. No sign of chewing on those exposed wires. Can't do the whole car tho. This is not the robust solution.
I have created a Metal Flashing (used for roofing) 10inches in height corral for the car with a back slide in insert for removal from the rear to move the car in and out with ease. It is "small" rodent sealed at the flooring of the carport and additional spread at that area, entirely coated with grease( rodents don't like grease odor). This has been in place since I got the car back from the rodent repair- now at 9 years. No mice/rats or their nests. But rabbits can hope over it (seen them) and they jump up onto the splash pan. They don't seem to bother anything and haven't built any nests. I just tap the pan with a stick and they high tail out. The only thing to pay attention too is having the right height of the metal wall for opening the car doors. It's all sort of a pain but worth the effort to live here.
Good Luck to everyone who has this problem
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