Maintenance and inspection (Audi 100 C3)

1. Check the coolant level in the system weekly and, if necessary, top up with a mixture of water and antifreeze to the minimum mark indicated on the expansion tank (photo). Check the level with the engine not running and top up when the engine is cold. (If the engine is warm, the level may be slightly higher). If the cooling system is sealed, topping up may be necessary in very rare cases. If this is not the case and frequent topping up is required, there is probably a leak in the system. Check all hoses and connector surfaces. If no leaks are found, it is advisable to check the system pressure, as there may be an internal leak.





2. With the frequency given in Section "Maintenance" at the beginning of this manual, carefully inspect all hoses, hose clamps, and visible system joint gaskets. Replace any hoses or clamps that look suspicious, and replace gaskets if necessary.



3. Check the condition of the alternator and water pump drive belts on 4-cylinder engines at the same frequency. Replace the belt if there are any cracks, and also check and, if necessary, adjust the tension of the drive belt.



4. At large intervals (approximately every 2 years), the cooling system must be drained, flushed and refilled with fresh antifreeze as described in Chapters 3, 4 and 5 respectively.