- Z axis rod guide do not work well with bearing, or Z axis lead screw do not work well with copper bolt;
- Wrong temperature measured by thermocouple.
- Replace Z axis motor assembly;
- Replace thermocouple and thermocouple wire.
- X axis rod guide is not vertical to Y axis rod guide caused by shipping impact.
- Adjust X Y axis rod guide.
- Nozzle or driver gear clogged.
- Clean the nozzle and driver gear.