Strange "striping" of extruded filament

After weeks of printing like a champ, my Taz2 has started exhibiting the following symptoms: regular “striping” of filament. It will start a bottom layer looking awesome, and then 4-5-6 or so stripes in, there will be a missing/clogged/terrible one, then good ones, then terrible…check these two photos to see what I mean:

the pattern continues up the print, to the point where my top layers are all gapped and patchy looking.

What I’ve done: re-re-re-leveled. Cleaned the extruder, cleaned the hobbed gear, re-adjusted the tension on the extruder.

At my wits end. What’s going on? It was producing beautiful prints, and one day just started this.

Try this Slic3r config and see how that affects things: You may also want to lower the Z axis endstop adjustment screw slightly, perhaps around a half a turn clockwise to increase your first layer height.

Are you using the same gcode?