Driver side floor leak after rain or car wash on 2008 Lincoln MKX

How do I troubleshoot a leak to the floorboard, driver side after a rain or car wash? This car is garaged so I know it's only after a rain or long car wash. Tips appreciated. Regards.

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1 answer 1 comment
clean the drain. its under the grills back of your hood... you have one on both sides...
Do I need to remove the plastic cover over the windshield wipers? Or, just use a car wash wand and spray directly into the grill. I tried to find the location to clean but was unsuccessful. Thanks.