Originally Posted by Mose

There might be something stuck in the housing, or part of the wall torn off or something that's creating drag. I'd just try a new piece.

Originally Posted by BCRider

And if you're buying new cable anyway spend the extra few cents and buy the ones with the slick ground outer finish On those the outer strands have been finish ground so they are all sort of like D shaped with the flat to the outside. The tend to slip in the housing a lot nicer and the extra contact area should result in longer housing life by not cutting into the inner core as badly.