Checking wastegate valve (1) with vacuum pressure
WARNING: This page is about a different car, the 2010 BMW 135i, 2009 BMW 135i, and 2008 BMW 135i. However, it is still accessible from the selected car via links, so may be relevant.
Wastegate valve must be opened without vacuum pressure.
The wastegate valves must close if a vacuum pressure is applied at the wastegate sockets (see BMW diagnosis system).
Check shaft on turbine wheel for rotatability.
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