Will stop/start cause turbocharger damaging

I have recently purchased a 3 Series BMW 320i Xdrive and assume it has a turbocharger fitted. With previous turbocharged cars I have always allowed a couple of minutes for the turbo to stop rotating and cool prior to turning the engine off. This BMW has an automatic stop/start feature and I wondered how protecting the turbocharger bearings fits in with the engine turning itself off.

Asked on 9 July 2016 by stupot1

Answered by Honest John
The stop start will not stop the engine if the turbocharger is too hot. These petrol turbos are also watercooled. It's only really necessary to idle the engine to cool the turbo bearings after a long ascent, after towing, after driving on a race circuit and after long runs at steady speeds on the motorway, but if the turbo is not too hot the stop/start will stop the engine.
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