“Burping” the cooling system in your Toyota refers to bleeding the cooling system and is necessary if air has entered the system. Air in the cooling system causes hot spots and subsequently overheating and serious engine damage. To prevent serious engine damage, take a few minutes to bleed the cooling system of air. Bleeding the cooling system in your Toyota is very simple and best of all doesn’t require any tools.
Allow the engine to cool down to ambient temperature.
Open the radiator cap.
Turn the engine on and turn the heat to max. Turning the heat to max allows the radiator fluid to circulate through the cooling system to ensure that all air pockets are eliminated from the system.