Subaru 2.5 FB25 head gasket seeping — white exhaust smoke
White smoke from the exhaust on cold start, coolant level gradually dropping, and sweet smell from the exhaust. The Subaru FB25 2.5 boxer engine can develop seeping head gaskets, particularly on the right-hand bank. This is less severe than the notorious EJ series head gasket failures but still requires attention. Using Subaru Genuine Coolant with its special head gasket conditioner formulation slows progression. Full head gasket replacement is the definitive fix.
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