Over time, rubber valve cover gaskets can degrade due to exposure to heat, oil, and chemical additives. Cracks, hardening, or even complete disintegration can occur, compromising the seal. Signs of a failing gasket include oil stains on the engine, a burning oil smell, or a drop in oil level Signs of a failing gasket include oil stains on the engine, a burning oil smell, or a drop in oil level Signs of a failing gasket include oil stains on the engine, a burning oil smell, or a drop in oil level Signs of a failing gasket include oil stains on the engine, a burning oil smell, or a drop in oil levelrubber valve cover gasket. It's crucial to promptly address these issues as an unchecked leak can lead to engine damage, including worn-out bearings, damaged pistons, and potentially catastrophic engine failure.