This is a friend's car. I replaced the condensor, compressor, and receiver/drier and flushed all lines about a year ago due to catastrophic failure. He has left the car with me over the weekend to work on a few other things. In working on the car, I discovered a massive leak of PAG oil coming from the vicinity of the receiver drier. Fortunately when I charged I used U/V dye, so tonight it was very apparent where the leak is coming from. It seems to be the little black pigtail that sticks off the top of the R/D; either that, or possibly a bad high-pressure line. I can't really tell, so I will go in there tomorrow morning and snug up the lines. But does anyone have any experience with the R/D leaking from that pigtail thing? It's not a pressure switch, as it doesn't have any wires going to/from it. It's just a black extension that protrudes from the top of the R/D.

See the picture below - it's the hex-shaped extension coming off the top. Any ideas?

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