How to Defend Your Vehicle Against Rodents

Rodents love your car’s wiring!

It’s true, rodents like mice, rats, and squirrels like nothing better than to climb up into your nice warm car and make a meal of your wiring harness. Air boxes make favored nesting areas for rodents, creating an unbelievable mess for us. Of course, this is nothing new. No one likes the cold, least of all rodents! Some new car manufacturers such as Toyota, Honda, and others use soy or bio-based ingredients in wire insulation, making wiring harnesses irresistible.

How do they get in?

Mostly they don’t. The most common area of damage is to the wiring harness under the hood. The engine block is nice and warm, a food source (your wiring harness) is readily available, and it shields them from the rain. It’s rodent heaven! They do sometimes chew through wiring grommets to get inside, but it’s rare. If they do find their way inside your car, it’s usually through the ventilation system. The air box that contains the cabin air filter is often where we find nests.

How do I know I’m sharing my car with rodents?

The most common symptom of a rodent damaged wiring harness is the check engine light. The ECM does a good job of keeping track of wiring and is usually the first indication that there’s a problem. Drivability problems including transmission shifting issues, stalling, or not starting can all result from rodent damage. Rodent infestation of the interior often results in odd odors from heater or defroster, and even bits of trash blowing out of the ducts when you turn the heater or defroster on.

How do I keep them out?

Start with cleaning your car, and the area where you park. Make sure nothing edible to a rodent remains. We had a customer with squirrel problems many years ago. It turned out she parked under an oak tree. The squirrels came out to harvest the acorns, and found a wonderful place to rest and snack under the hood of her car! She changed her parking arrangements, and her squirrel problems were no more. Mice and rats usually use the tires to gain access to your vehicle. If you put a mouse or rat trap by each tire, you can resolve your rodent problem in a few days. There are sprays and powders available that are purported to deter rodents, but it’s our experience that they don’t work very well, if at all. We’ve also heard that you should attempt to block potential entry points but that’s ridiculous and impossible! Bottom line, make your car as unattractive to rodents as possible and get the traps out at the first sign of trouble.

Big Oak Citgo has knowledgeable technicians to deal with these types of repairs as well as ready your vehicle for state auto inspections near Yardley, PA, and other nearby areas.