Ender 3 underextrusion I am a beginner in 3D printing and recently bought an Ender 3. With the filament included in the package, my first print ever was flawless. However, after the first print, I tried printing with ABS, which did not work out, so changed to PLA, and ever since then, all my prints were under extruded. I have tried everything. I bought a new nozzle to make sure it wasn't clogged, I cut the last 20&nbsp;mm of the PTFE tube, I performed cold pulls, I leveled my bed before every print, made the line width in the profile 0.48&nbsp;mm instead of 0.4&nbsp;mm, increased the flow, tried printing with every temperature between 185-210&nbsp;&deg;C, looked at different Ender 3 suggested profiles on the internet, and more. I also made sure there was nothing wrong with the extruder. Attached are pictures of my most recent prints. Anyone who can tell me what I am doing wrong???
The helical exterior is an indicator of a filament diameter mismatch or volumetric mode enabled for linear commands

From ref:


  Then you probably enabled volumetric extrusion by accident.
  
  On LCD go to
  
  
  Control
  Filament
  Disable
  Save EEPROM
  Revert estep cal if applicable.
  
  
  What is it? M200
  
  Its a feature of Marlin firmware which interprets E moves as mm3 instead of linear mm. It is poorly described in the menu, and tends to be enabled by accident.