IAC missing cap or plug 96 windstar 3.8

Does anyone with a 96 3.8 have a brass tube on the back side of the iac (toward engine) It looks like a vacume line should hook to it. I believe its a vent. If I blow air into it it passes air both directions. Or is a cap missing from it? I looked on alldata and it shows it to be a vent but it shows some kind of a filter. Any ideas?