I am still doing those 3-5 hour prints. I had this happen on another print, on seconds where a lot of retraction was happening, the filament would skip on the hobbed bolt… I paused it and tightened the bolts on my wade accessible extruder but this is really bad and will probably break at this layer of voids. The spring pressure is so tight that I couldn’t pry the idler part open after tightening. There is likely some median tension that I need to find.
Have you tried to lower retraction speed? Which slicer are you using?
I am using Cura and the retraction speed was on 20mm/sec by default.
Was the cooling fan on high?
It is on high all the time after the first 2 layers.
The spring should be compressed so that if you take some dial calipers to it the measurement would be about 6mm. This is a good starting tension. Also how old is your filament and what type of claimant is it exposed to? If there is a lot of moisture in the air this will cause abs plastic to expand in diameter slightly. It this happens you will need to recalculate the esteps per mm in the firmware. I assume that you are using an Arduino mega board ether ramps or Rambo. If you are using printer board the process is the similar you will need access to the firmware settings (yours is probably marlin). This tutorial is for Rambo but the idea is the same.go to Lulzbot.com and under the support tab select OHAI-kit on the righthand side of the window. While inside the OHAI-kit pop up link, select the icon that says “calibration” and then “single extruder calibration”. Again, this tutorial is for Rambo users but the esteps process is the same. you can also find troubleshooting information on the REPRAP wiki.
Good Luck 
I’ve been keeping my filament spools inside a “rubbermaid” tote container, while not completely air tight, I have some large dessicant packs in there too. I picked up some gallon sized ziplock bags and will seal it up in there with the silica gel bags. Very rarely do I hear a pop from the extrusion. This is PLA I got from MicroCenter. I carefully looked for a bag that looked like it was without holes. This filament is working much better than the black PLA I got with my printer from makerfarm. Using RAMPS and have not connected the machine to a computer yet. I have been printing off the SD card. I ran a manual test of extruder E steps and I am underextruding 3%. Unfortunately it looks like there is no way to commit the changes into the firmware (M500??? I have watched some youtube videos on Marlin firmware settings) without using a PC and something like repetier host.
@Charles_Reiche you said you are using Cura. I had to set the Extruder steps per mm in cura. It looks like cura sends those adjustment Mxxx commands.