Where does this connector go.

[Raksolid]

I have a 2001 Expedition, 5.4L. This connector isn't connected and I don't see a spot for it to connect to. Is this something that needs to be connected or is it for some sort of add on that I don't have installed? It's located next to washer fluid reservoir. The two connectors running to the reservoir are already connected so not sure if I need to worry about it or not.

 

[Hamfisted]

Looks like the air compressor plug ? Did the Expy originally have air suspension ?

 

[Raksolid]

Mine does have an air suspension leveling system. It makes noise and stuff from time to time when it turns off and on by itself. I did look over in that area by the air pump but didn't see a disconnected plug.