Should we idle our turbo after a motorway journey?

I understand the issue with red-hot turbos carbonising the oil if they are switched off immediately after a motorway journey, especially with diesels like ours. How long should they be idled before switching...

Should I idle the engine of my petrol car after a long run just like you advise for turbo diesel owners?

You have wisely advised owners of diesel turbo cars to idle the engines after a fast run before switching the engine off. Is the same advise also applicable to petrol TSI cars, such as the Volkswagen Polo...

Why is the idling irregular when my 2003 Vauxhall Zafira starts up from cold?

After 140,000 miles of reliable use, my wife's 2003 Vauxhall Zafira 2.0 DTi is misbehaving. At temperatures below 8c it starts instantly and fast idle is fine but as it warms up and the idle speed drops...