Extruder Skipping / Clicking

This can be due to a few reasons:

-Running to fast
Solution: Do not run printer over 120mm/sec

-Trying to extruder too much Extrusion multiplier set to high
Solution: Check that you are extruding the expected amount.

-Motor not tuned
Solution: Following tuning guide

-Mechanical issue
Solution:Check the drive gear is lined up and nothing is binding

-PTFE tube worn out or pulled out well the filament was not up to temp
Solution: Replace tube

-Printing layer near or at the nozzle diameter (not recommended)