[lidation]

My '13 X3 w/ N20 engine (117k miles) found some oil leak while I was overhauling the cooling and intake system.

I found fresh oil stains behind the water pump, under the turbo. The turbo itself is dry and not dripping. The oil seems to be from the engine block. However on the engine block wall above the turbo it's dry. The valve cover gasket was replace 40k miles ago and it doesn't show signs of leakage. The leak is very small and not dripping (my underpanel doesn't show any oil drips.) but this still worries me.

What could this be?

[lidation]

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