Ender 3 Pro extruder drive rocking back and forth I've been running this Ender 3 Pro for quite some time with no problem up until recently. The issue was the printer refused to extrude filament (the extruder stepper seems to be rocking back and forth) so I went through a few things to try and fix the problem:

I leveled the bed properly
I printed at higher temperatures (215 °C for PLA which is the only filament I run in this printer)
I cleaned the nozzle and I actually replaced the nozzle with a new 0.4 mm nozzle
(same size as before)
I replaced my Bowden tube with a newer one (unbranded) and even replaced the tube fittings for the extruder assembly and the heat sink.

I saw somewhere that maybe the wiring to the extruder gear is frayed but I inspected the extruder side of the connector and everything looks fine. I would open up the box and everything but I want to see if anyone has a solution before opening up the circuit  box.
Sounds like one end or the other in your stepper cable is not seated correctly or has shaken loose there are 4 wires if even one doesn't make proper contact you will get a shaking back and forth almost like a hard vibration. I always take a cable from one of the other steppers plug into this one move the motor with good stepper wire 10-20&nbsp;mm see what motor does if it is okay then you know it is a cable issue if not, it could be a bad board or stepper.