Checking Cooling System For Leaks/Checking Fill Quality (Particularly On Systems With Thermal Management)

Information 

• If the coolant level drops significantly during the test and there is a danger that the reservoir will be emptied, the cooling system is not filled correctly (air bubbles in the system or vacuum filling not carried out  sufficiently, for example).
• If the coolant level drops only slightly during the test, the system is filled correctly. 

Information 

Possible symptoms of an incorrectly filled cooling system include (air bubbles in siphons) => 

• Little or no heat output. 
• Noises from the dashboard/switch panel close to the heat exchanger ("gurgling, glugging"). 
• Sporadic low coolant level indicator. 
• Implausible engine temperatures (jumps, fast fluctuations in the instrument cluster). 

1. Check the cooling system for leaks. To do this, apply a test pressure of approx. 1.5 bar using the > V.A.G 1274B - Tester for Cooling System and check the hose connections for leaks. The pressure must not drop.

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.

   Cooling system tester

2. Check the engine coolant level. If necessary, fill the coolant reservoir with coolant up to the maximum marking. If there is considerable coolant loss, the cause must be investigated.

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.

   Coolant reservoir

3. Screw on the cap of the coolant reservoir again until it locks with an audible click.

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.

   Cap on coolant reservoir

4. Close the maintenance flap.
5. Check radiators for external soiling. The radiators should not be excessively dirty. If necessary, they can be cleaned using a vacuum cleaner with a brush attachment.