Help with my prints!

[JonDoherty 0]

I got my Creality Ender 3 about a month or two ago and I've been having this problem. I've been printing for a while and my prints have missing lines in them every few layers. I have tried changing extrusion but that doesn't seem to work. Maybe temperature? I have no idea, please help. =\ 

Edited October 9 by JonDoherty
forgot to add picture, added tag

[gr5 1,075]

That's underextrusion.

 

Those gaps are most likely due to the Z axis moving too far suddenly.  If the Z axis moves too far then you basically have underextrusion.  However it could be that the filament is too tight in the bowden (varying filament diameter) or tangled filament or a few other issues.  But it looks like each time it's an entire layer.  Maybe you could verify if those lines go ALL THE WAY around or not.  If not then it's not a Z issue.

 

Z issues are a pain to figure out.  Usually bad bearings/sticky bearings or bad Z nut or bad z screw(s).  If the bed moved up and down I'd say put a brick on the bed to see if it makes it much worse or much better and if so it's a Z issue.  But I don't think you have a bed that goes up and down so I really have no idea.  This is an Ultimaker/cura forum.  Not a creality forum.