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Does the stop-start system still operate when a hot turbo needs to be cooled down with the engine running?

I understand the objective of stop-start, but it seems to contradict something I have always done after a long or fast trip: leave the engine to idle for a few minutes. I can’t remember why exactly I do it to be honest, but somehow it seems to make sense. How does this work when, after a fast trip, it could now cut out at the traffic lights or whatever?

Asked on 6 February 2012 by NW, via email

Answered by Honest John
If the engine is turbocharged, it needs to idle for a minute or two after a long ascent, after towing or after a long motorway run in order for the engine to pump oil through the turbo bearings to cool them down and keep them lubricated while the red hot turbo spools down from something like 150,000rpm. Engines with stop/start generally do not stop when sensors detect that the turbo is too hot.
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