kenoshakid:
To address the question you asked: I would give it a thorough cleaning using a high-alcohol beverage. (My preference is Bacardi 151.) Remove the stem. Dip the end of a pipe cleaner in the Bacardi and run it through the shank and stem. You will need multiple pipe cleaners for this. Be absolutely careful not to drip any of the alcohol on the outside of the pipe; it can ruin the appearance.
If your pipe has never gotten a really thorough cleaning before, you might also benefit from running a shank brush -- also dipped in the alcohol -- through the shank to scrub away anything that has been building up there.
Then run dry pipe cleaners through the stem and shank. When they come out clean, you're done. Replace the stem, and allow the pipe to dry out -- I would allow at least a week -- before smoking it again.
If this doesn't solve your problem -- and this is a cleaning process I do on all of my pipes at least twice a year (which is in addition to cleaning each one with a dry pipe cleaner after every bowl) -- then I would recommend using the salt/alcohol treatment, which is described elsewhere here. (Sounds more complicated than it is!)
But I also want to comment on the question you didn't ask: How did this happen? It may be the result of not running a pipe cleaner through the shank after every bowl to remove moisture. Or you simply may be overdue for a thorough alcohol cleaning. It may have to do with smoking this one pipe too often and not giving it enough time to rest/dry out between smoking days. (I'm not sure it would hurt anything, but I try not to smoke the same pipe more than three times on any one day. . . and then it gets at least a week's rest between smoking days.) It may also have to do with storage: Your pipe needs air circulating around it in order to dry out between smokes; it shouldn't be kept in a drawer, say, or enclosed in a plastic bag.
One final note: Do NOT use a commercially sold "pipe sweetener" instead of a potable alcohol. These "pipe sweeteners" are almost all awful and although they will "clean" the pipe, they will likely leave your pipe with a bad chemical taste. (They used to be much better, but the few I've tried in recent years shouldn't be allowed anywhere near a tobacco pipe. But they might work fine on a plugged toilet.)
Hope this helps!
Bob