Vertical lines with no layer adhesion I have an Ender 3 Pro which I use together with Cura 4.2.1 (and Octoprint). I print in PLA at 180°C. The print bed is set to 70°C. The Bed temperature is lower though, since I use a glas bed on top of the heated bed. I use a print cooling fan at 100%. The layer height is set to 0.2 mm, the line width 0.4mm from the 0.4mm nozzle. My retraction is 5mm at 50mm/s.

Prints come out with heavy vertical lines and no layer adhesion at these lines. I can easily break the print apart. In other spots the print is fine. Any ideas on what could cause this problem?
The Ender-3 has a problem that stems from the way the X-axis is mounted and which can often be a source for "jumping" in the  Z area. Seeing the upper photo, you can see that the bad printing seems to be on one side more than the other, leading me to believe this might be the reason:

Check if the X gantry is orthogonal to the frame on both sides and make sure the eccentric nuts are not too tight so that the wheels roll easily on it, but not spin freely.

A little drop of oil on the Z-rod might also help to remove any binding, making sure that it moves smoothly.

If your layers are bad repeatedly, it also might be a problem with the extruder. Check if the extruder arm is all intact. When I had such an issue that was recurring every 10 layers, I found the lever arm holding the wheel on it broken and occasionally loosing contact. If it is broken, I suggest swapping the extruder assembly for a metallic one.