A Cozy Place
There was one site that explained “they’re attracted by the warmth of the engine, which creates a cozy place for them to nestle. Squirrels create a fine mess once they bring in nuts, acorns, and nesting materials.”
Damage
But this could lead to damage and problems. Canadian Wildlife Federation said that it was a very common issue, especially in rural areas. They suggested that to decrease the occurrences of the incident we need to leave the car hood open so the vehicle would be cooler.