While you’ve been sheltering in place, rodents may have sheltered under your hood. In the last couple of months, we’ve seen five or six cars with wiring damage along with remnants of nesting, eating and “visiting the powder room.” Some cars have very complex wiring harnesses that must be replaced as entire assemblies - expensive parts and extensive labor. Sometimes, the first evidence is a rough idle, a check-engine light, bits of plant material under the hood, or a telltale smell. These cars usually require a thorough cleaning of the engine compartment, some diagnostic work, replacement or repair of wiring, and some preventive measures. We recommend wrapping wiring harnesses with capsaicin-impregnated tape (it’s spicy hot) to deter rodents from chewing. Rodent repellents, containing odors rats don’t like such as mint, and fox-urine pheromones, can help a bit, and you can install under-hood strobe lights or ultrasonic “noise makers” to make your car a little less inviting. Put granulated repellants in little sachets made from nylon hosiery and tie them in a few spots around the engine compartment, but be sure they are nowhere near rotating components or hot spots. We can’t speak to the success of these measures, but we can help you use them safely. Even better, pop your hood regularly and look around. If you see droppings, puddles of urine, leaves and shrubbery that look like a critter dragged them in, bring your car to us and let us take a closer look. If you catch the little interlopers when they first move in, you may prevent a very costly repair.