Ahh i think i follow you.
Least its a normal thing was beginning to worry.
Is there anything you can do or not really? Like you said u get a few seconds of high revs sounding diesel'y then all hunky dorey..
While im asking things do you need to let the turbo warm up/cool down before moving/turning it off?
Ive heard mixed things on this so far im leaving it about a minute before turning off.
no not really, it wont get any worse,
as for the turbo, give it 10-15 mins of steady driving first thing , even when the coolant temp gauge says 90 the oil temp still isnt up to running temp,
once warm dont be scared to use it, as long as its running a decent oil/well maintained it'll take near on everything you throw at it, ive done 32-33k in 18 months of hard driving and its not missed a heatbeat ( not one for tempting fate!)
plus when you come to shut the engine off you're best bet is to drive the last 2-3 mile of your journey gentle then the turbo will have cooled down,
damage is caused by shutting off the engine if the turbo is red hot/practically glowing since theres a constant flow of oil running on the bearings, if you shut the engine off when its red hot, this oil in the turbo can clog up and block oilways, a surefire way of killing your turbo in a short period,
as long as its warmed up and cooled down after you shouldnt have any problems