I'm going to presume you are talking about the motor driving the car's air ventilation and heating / cooling system inside the passenger compartment. Typically, it's located underneath the heat exchanger. Usually found right against the engine f...
A carbuncle is a cluster of boils, draining pus onto the skin. It is usually caused by bacterial infection, most commonly with Staphylococcus aureus or Streptococcus pyogenes, which can turn lethal.
Head Gem: The shiny ruby set in a carbuncle's head is actually a part of the animal. It's value can be 500 gp (70%), 1,000 gp (25%), or 5,000 gp (5%). These values are doubled for medium size carbuncles.