Hey Eraserhead,
I doubt if it is your slave cyl. The master can still be full of fluid and be no good. mine was. I did get a new line at the dealer for only 150.00! ha Some plastic and 2 fittings. I was still glad to get though. The quick disconnect was actually pretty easy to take apart. Just dont force anything. Put some pent. oil on it and wiggle slightly forward. There are 3 tabs on the inside, sliding the the plastic sleve will compress the tabs for removal. Similar to a fuel filter replacement. Just dont force it!!!