My P1S suddenly started printing with weird artifacts

Hello everyone! My P1S suddenly started printing with weird artifacts:

It was printing just prefect yesterday with absolutely the same settings and the same filament (same spool). The same model printed yesterday:

Any idea?

Thank you!

Have you performed the rod cleaning maintenance which includes retensioning the belts? I have seen the same pattern when the carbon rods get a little “sticky”.


Thank you for the advice, but I clean the rods and do other cleaning/tuning maintenance regularly. Today I figured out it’s AMS related since the issue reproducible only with one AMS slot. I think it looks more like under extruding and it could be caused by clogging or some other mechanical issue with the first stage feeder. I just took apart my AMS and it didn’t find any clogging or other abnormality . will try to clean it and try once more.

The problem seems to have been solved by disassembling my AMS and cleaning the first-stage feeder. I’m not sure exactly what caused the problem though.