How is the turbo in this new design cooled? Sometimes when I restart a hot engine, there is a high pitched whirling sound before I take off. Is this the turbo in action?
Are there active shutters in this car?
You might want to post this on one of the BMW forums, not many folks here will know the detailed workings of BMW turbos.
I would imagine it’s oil cooled and the high pitch sound would be the fuel pump or maybe the turbos are spooling up to let the oil flow through them to cool them off a bit before you start off.
When/if you run the car pretty hard, do you sit and let the engine idle for a little while?
What are proples’ definition of driving hard? There is 10 minutes between my home and the freeway when I drive easily before shutting off the engine.
Driving hard is when you stomp on the gas and wind the turbos up. About the only legitimate time to do this is when you are merging onto the freeway. But you may want to get your ya-yas out at other times, too.
The high-pitched whine is the turbo(s) spinning up. If you use full-synthetic oil of the recommended weight, change it when you should, and give the turbo(s) a cool down period of a minute or two with the engine idling after a hard run, you will extend their lifespan.
i believe it also mentioned a long period of time on the highway as well, so depending on how far you travel…