there wont be a drain for the fresh air intake for the a/c that im aware of.. its designed to take air in only, but like i said, if the gasket is trash it will leak.. im not sure how yours will look. here is mine from the outside here is how it looks one my old lincoln while the hood is popped i was also thinking.. did you buy it new? if used.. i have gotten ahold of cars where people popped the rubber circles off.. for what ever reason.. but they are used to drain a flooded car, i have also seen fools with thair power wires ran in the dorr jam cause the same problem but im sure thats in no way your problem hope you find the issue