Streaking? Extruder? Power supply? Controller? Slic3r? Other Issue?
I've been having a lot of different issues with my printer for a little while now (fix one after another) but this issue is making me scratch my head. The most recent issue was globbing occurring (looked like material was oozing out out around the heat block) which would besides depositing globs cause layers to be missed and the globs could also cause layer shifts (as the printer hits it and then catches for a little bit). So I decided to replace just about everything on the hot end side (did a couple of other little upgrades too). Everything was printing well for about 2 or so prints... then there started to be a couple of odd issues, I fairly consistent lack of material being placed (see images below) and occasionally the y-axis endstop won't trigger (it's easiest to see the effect on a larger print) but the quality of all my prints have become worse. I've tried a few different things:
Editing flow rate, temperature, first level z-offset
and old g-codes that used to print well before (even the first layer cal print has issues).
I'm on a battery backup with current/power conditioning (as without it was a problem for layer shifting way back in the day). I can't "feel" any issues with the extruder (but it may be such a small movement that I cannot tell). Given it has issues with the y-axis endstop I'm worried it may be something that won't be an easy fix (but the Y endstop has failed before and I've replaced the switch for it, so it is possible that's going again, which means they are not related?).
I will probably try a few more things over the week: flash firmware, disconnect everything from power for a few days, reformat SD card; just not sure what exactly it is but based off of these images it seems like it has become someone regular in interval.
I think I'm seeing the same problem. One day it was good, next day, same file same filament same everything, I get this periodic loss of flow causing gaps in perimeters. Despite many adjustments, full nozzle clean, extrusion multiplier recal and many test cube prints they all have consistent marks. Smaller layers, lower speeds, higher/lower temps, different filaments (all PLA) no good.
Your issue looks like a worse version of mine.
I hope someone can point both of us in the right direction.