Originally Posted by Eleventeen
+1 on the bad turbo. Just becasue they don't find any "leaking" doesn't mean the exhaust side of the turbo isn't passing oil. The reason it would smoke is because the turbo would burn the oil off in the hot exhaust, so your evidence literally goes up in smoke. The oil dump usually happens during deceleration with a bad turbo seal. Smokes when you come to a stop, but looks okay while cruising. As it gets worse, you'll also get a big puff on initial acceleration, after the car has idled for a minute, but then the smoke goes away until you stop again.
I suppose you could test/check for a bad turbo by driving up higher into the rev range on a cold engine (4k should suffice), then let off the throttle and coast down a couple of times. Put the car up and pull the exhaust off the DPs and look for oil wetness in the DP, since the exhaust probably won't be hot enough to burn it off if you do it shortly after a cold start.
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