My guesses would be either water in the cable that froze or it's pinched somewhere from factory. Mine seized up after about 16-17 years. They weren't too hard to change, but they are tie-wrapped somewhere in the tunnels, so take your time and don't force anything. Also, mine had decades of dirt and grime in the tunnels, and yours will be nice and clean, so that's good. I changed both the choke and throttle cable as a pair. There's a specific order in doing it to make it a lot easier on yourself. As I recall, I had to take them out at the dash board, pay attention to the spacers behind the dash on one of the cables if yours has them, or the lever will hit the steering wheel when you re-assemble in incorrect order (ask me how I know this). I had to cut the old cables off of the levers, tape the end of the new cable to the cut off end of the old cables, and use the old cables to pull them through. They'd get stuck every time I hit a tie-wrap. Took some skinny hand to get into the tunnels to cut them. But I think it ended up being less than an hour job.