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Oil smoke from the exhaust

As im hunting down the reason for the exhaust smoke, im asking it from the forum also. At first, there was some extended vacuum inside the engine and it was hard to get the oil cap off with working engine. So i found some broken vacuum hoses and also the PCV valve was fckd, changed them and the vacuum under oil cap was much much better (i think its normal as it is now). At first it felt like the smoking from the exhaust was gone also with the fix, as its known to smoke when the crankcase breathing sytem is not right.
But for my sadness its still smoking now, so my next suspicion are the valve stem seals now. BUT, as much as i know, it have to smoke at first startup from cold after sitting some time (like all night), isnt it so? There are no smoke whatsoever from the cold start and with the cold engine at all. After the engine temp is warm and the oil temp is getting warmer, its starting to smoke. To describe the smoking a little, its doing it when you are getting away from the standstill or accelerating with lower rpms, BUT with the light throttle. Under heavy load its not smoking, also if you are pressed the gas couple of times its not smoking under light load also anymore. After cruising normally some time and then accelerate lightly again with the low rpms, again theres coming a puff of blueish-white smoke cloud out of the exhaust. What it can be, is there some error with the crankcase breathing or more like valve stem seals? I hope someone can jump in for this thread and have some ideas how to test it.

To clarify, its S6, so N/A engine. Just changed out the spark plugs and they was fine looking, no oil on them or inside spark plug holes. Forum Index -> Audi S6 & RS 6 (C5) quattro
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