probably due to a worn timing chain.
to check:
when starting from cold (first thing in the morning) listen to the engine noise if it gets a lot quieter after 5-6 seconds of running it's due to the timing belt being worn.
the timing belt tensioner is oil pressure powered it takes up most of the slack after 5-6 seconds when idling it lossens up again (though not as much as when cold) causing slight mistiming not enough to affect running but a build up of unburnt gasses occurs causing white smoke for a second when you set off.
It happened on my 208d 1996. replacing the chain cured it -
find a garage that knows how to replce it by threading off the old belt and not removing the head - it saves hours and hours on labour charges - mine took 40 minutes instead of one garage which quoted 14 hours labour! cost of belt £15 labour was £75 a bargain - hope that helps!
Graham
October 2007
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