Volvo XC90 D5 Oil Leak Due to Valve Cover Gasket Failure

To diagnose a valve cover gasket leak on the Volvo XC90 D5, first remove the engine acoustic cover. Inspect the perimeter where the valve cover meets the cylinder head for signs of oil seepage, wetness, or dirt accumulation. Use a flashlight to trace the oil trail upwards to ensure it originates from the gasket line rather than a leaking oil filler cap or high-pressure fuel pump seal.

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