2003 Ford Windstar Sloshing noise under top of dashboard

I have taken this car apart looking to get at the sloshing sound under the top of the dashboard. I'm stumped. And it smells like old plants after the car sits awhile. I removed blower fan where AC condenser is and it's TOTALLY DRY. I flushed cowling drain where water rolls of windshield, now totaly clean. But I still get that damn sloshing noise when I zig zag slowly down the road. There is something directly under the dash that is holding water. NO WET CARPETS, no sign of anything wet. Just the slosh and the smell.