If you are lucky, it is the valve cover or more likely the oil cap gasket. Clean the engine so you can check there and some other usual suspects…:) Once clean, check the camshaft and crankshaft seals in the front. Another leak spot is the rear of the head where a plug is installed (some 7 and 940’s have distributers there). Plugs used there in 240’s instead to fill hole.

Yes, the breather system (including the flame trap, breather box and related hoses) are known for clogs and subsequent excessive crankcase pressure. If you don’t know the car’s history, buy at a minimum a new flame trap and its hoses. The hose that runs from the intake manifold to the flame trap is a common culprit for clogs (my 90 240’s problem that took forever to find!). As is the hose from the flame trap to the breather box. If you don’t fix excessive crankcase pressure it will simply blow through any new seals again.

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Will I buy another Volvo??? We'll see....