Is idling good for a diesel engine?

I haven't owned a diesel car before, but last week bought a 2014 Audi A5 2.0 TDI. A friend advises that I should let this car (with 1200 miles on the clock) idle for five minutes on the drive after using it at normal working temperatures (especially after a motorway run). He says this will enable the turbo to cool down and avoid oil degradation. Is this correct?
Yes, but two minutes is enough: after towing, after a long ascent, and after motorway cruising (such as when you stop to fill with diesel). If you live five miles from the motorway then the gentle drive from the motorway back to your house will do the job.
Answered by Honest John on

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