Antifreeze mixture (Audi 100 C3)

1. The cooling system is filled at the factory with an antifreeze mixture that contains a corrosion inhibitor. The antifreeze mixture prevents freezing, raises the boiling point of the coolant, and the corrosion inhibitor reduces corrosion and scale formation. For these reasons, the cooling system should be filled with antifreeze year round.

2. Any good quality antifreeze is suitable, as long as it has ethylene glycol and contains corrosion inhibitors. Do not use antifreeze based on methanol, because these mixtures have the disadvantages of being flammable and evaporating quickly.

3. The concentration of antifreeze must be such as to provide the required level of protection, selected from the table given in Specifications.

4. When refilling the cooling system, always use the same water/antifreeze mixture that is already in the system. Refilling with water alone will gradually reduce the concentration of antifreeze and reduce the level of protection against freezing and boiling.

5. At the beginning of the winter season, check the concentration of antifreeze in the coolant, and add clean antifreeze if necessary.

6. The antifreeze mixture should not be used in the system for longer than the manufacturer's recommended period, which is usually no more than two years. At the end of this time, drain the system and refill with new mixture.