Buick Lucerne water leak in front and back passenger side floorboard not corrected on Buick Lucerne

Some Buick Lucerne owners report experiencing water leaks in both the front and back passenger side floorboards, which can stem from various issues. These owners often find that inspecting rubber seals and window lining reveals gaps or damage that allow water to seep in. Additionally, checking seals and weatherstripping, including door and sunroof seals, is crucial for identifying potential leaks. Some owners have discovered that testing the sunroof drainage by pouring water on it can indicate whether it's functioning properly. A damaged windshield seal may also be a culprit, especially if leaks occur after washing the vehicle or during rain. Furthermore, a clogged A/C condensate drain tube on the passenger side can lead to water accumulation on the floor. Other contributing factors include leaking sunroofs, failing windshield gaskets, clogged wiper cowl drains, and malfunctioning heater cores. Owners are advised to systematically check these potential sources to effectively resolve the water leak issue.