7 Reasons Your Cars AC Is Not Blowing Cold in San Antonio, TX. #1 You've got a leak in your AC system. Simply adding refrigerant will not fix the problem for long (If at all). #2 Until you know the source of your AC systems leak it is impossible to judge how much it will cost. #3 Your car or trucks AC can freeze up even when the temperatures outside get over 100 degrees. #4 That annoying click coming from under your dash (especially if you own a Ford F150 truck) needs to be r