i have diesel in my sump and plenty of white smoke
the diesel fuel to crankcase can only be found in a few locations..the throttle (haven't got any info to refer to) must be located above the crank case....check the gaskets on the throttle plate there...must be a leak on the liquid side~
Been reading on several 2005 Peugeot 407 sites talking of faulty/dirty injectors causing similar issues.
the throttle plate deals with air...no fuel....that's what I thought, but these "FRENCH" designs get you comin' and goin'...where did you find that info? your public library? dandy-
Some also talking of bad turbos and blown head gaskets causing smoking issues? Hope this gives you some areas to look into.
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