Sounds like valve stem seals to me. What happens is the oil accumulated in the top end seeps down into the cylinders, say after an overnight sit, then burns off at start-up. Not to be confused with valve guides, these are a real PITA to replace, but it is a DIY job, about an 8/10 on the difficulty scale with the right tools....

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1986 560SL
2002 Toyota Camry
1993 Lexus