Cooling liquid (Audi A6 C5)

The engine cooling system must be filled with a mixture of water, antifreeze and anticorrosive agent. Additives to the coolant prevent the engine block from freezing and the formation of corrosion and limescale, and also increase the boiling point of the coolant. Due to the fact that the cooling system is of a sealed type, when the coolant is heated, there is excess pressure in the cooling system, which also contributes to an increase in the boiling point of the coolant. The pressure in the cooling system is limited to 1.4-1.6 bar by a valve in the expansion tank cap.

It is not recommended to use the previously used mixture of antifreeze and anti-corrosion agent G11, which is green. It is prohibited to mix anti-corrosion agents G11 and G12 A8D (red color), as this may cause serious damage to the engine.

Note: If the cooling system was filled with a coolant not recommended by the manufacturer, drain it from the cooling system. Fill the cooling system with clean water and run the engine at idle speed for 2 minutes. Drain the water from the cooling system and blow compressed air through the expansion tank into the engine cooling system. Fill with fresh coolant recommended by the manufacturer.

Attention. When adding liquid to the cooling circuit - including in the warm season - use only a mixture of VW antifreeze and anti-corrosion agent "G12" (red) and clean water with a low lime content. Even in summer, the proportion of antifreeze in the coolant should not be less than 40%. Therefore, when topping up, add antifreeze.