Updated July 2026 Many drivers first hear about soy-based wiring after discovering chewed wires, warning lights, or a rodent nest under the hood. Repair shops and online forums often blame modern wire insulation made with soy-derived materials. Some vehicles do use plant-derived materials in components, including certain plastics, coatings, foams, and wiring-related materials. But the claim that mice chew automotive wires because they taste like soy goes further than the available evidence supports. Quick answer: Soy-derived materials may be used in parts of some modern vehicles, but rodents also chew conventional plastic, rubber, foam, and petroleum-based wire insulation. Cars attract More…