I might have put this in the wrong section, so I'll just post the same topic again here. If anyone sees a thread with the same title somewhere else, delete it.

So while everything about the printer works fine, the E-Motor is not moving the filament through the nozzle. I manually step it 1mm at a time and nothing comes out. The filament goes through just fine, so there's no clogging or expanding or anything, and the motor is running fine, but there is no friction between them.

Can someone please help? i know I assembled it correctly (I upgraded to the MK8 Pro, so I dunno if that's any different.)

Not sure if this helps as your problem description is not very specific. But last night I was testing myself the cold extruder of the Prusa i3 I'm building and ran into the following. I was giving "G1 E10" commands and the filament was not moving at all. Till I realized the E10 were absolute coordinates. Switching to relative coordinates with "G91" solved it. Now the extruder was feeding 10mm with each "G1 E10" command.

Well, I'm one step closer to fixing the issue, but there's still a problem. The extruder was missing a spring and the guide wheel, which I added, but there's not enough friction between the filament and the motor to push it down. I can hear it whirring when I manually move it 1mm while the PLA is heated, but there's no plastic coming out the nozzle.

As for what you said, I'm not sure I understand cause I'm not familiar with how to adjust the firmware.