Originally posted by KansasHorizons.com I tried switching back and it wouldn't go or if it went somewhere it would jump around from 4 to 20 seconds.
This part makes it sound like the typical e-dial issue, which is common with the K-r and some other models. There could be something gunking it up, or excess lubricant on the e-dial mechanism causing it to skip. Would it kick you out of bulb mode if you rolled the wheel yourself during a shot? I've never attempted that.
The fix is normally a squirt of clean drying contact cleaner (the kind without any added lubricants), followed by rolling the wheel for a few minutes in each direction. Since the K-5 is weather sealed, I don't know if it would be that easy, but that's the process for other models, and it nearly always works.