17 00 010 Checking for leaks between cooling system and combustion chamber
WARNING: This page is about a different car, the 2006 BMW X5, 2005 BMW X5, and 2004 BMW X5. However, it is still accessible from the selected car via links, so may be relevant.
WARNING:
Danger of scalding! Only perform this work after engine has cooled down.
CAUTION:
When engine is running with cooling system depressurized, this can create steam bubbles. These cause the engine to overheat. Observe coolant temperature.
Check for leaks in cylinder head with CO leak tester.
In the event of a leak, the color of the test liquid turns yellow by the carbon dioxide (combustion gas) entering the cooling system.