Definition: Retrofires are a type of fire that occurs when a chemical reaction in an engine or fuel system releases excess heat and gas. Retrofires can occur due to a variety of reasons, such as improper maintenance, malfunctioning equipment, or incorrect fuel delivery. They can also be triggered by external factors such as high temperatures or vibrations. Retrofires can be dangerous if left unchecked, and they require immediate attention to prevent further damage to the engine or other components.