ok so i found a leak on my passenger floorboard that i assumed was my heater core so i plugged the hoses and the leak went away. but that was during winter. so i just pulled apart my dash and took the old heater core out and pressure tested it and it doesn't leak at all. what else could have made that leak happen. i have heard that it could be the AC condensation run off being held up by a clogged drain hose. i will be checking that ASAP but i don't know what else it could be please help wahh

 

If/when a heater core leaks, the windows will fog up and make a slimey mess when you try to clean the glass. It usually has a sweet smell as well. AC condensate drain could be clogged with debris. PITA to get to... above the right frame rail, bottom of the evaporator housing. Use a plastic drinking straw to clean it out, metal tools may puncture the evaporator. The drain usually gets clogged with leaves or pine needles that make their way into the cowl by the wipers. Or maybe a mouse made a home in there