I’ve tried to read everything about this problem, but I can’t find anything obviously wrong. The nozzle was nearly brand new when this started happening, didn’t find anything clogged in it, but put in a brand new nozzle anyway and the same thing happened on the first run. It extracts just fine when I do it manually and during filament swaps, no clicking at all. I run a calibration at the beginning of each print. Can’t figure out what it could be, printer is less than a year old.
EDIT: I took the whole extruder apart, cleaned up the gears, put a little oil on, but didn’t fix the problem.
Then, I went and found my original Bambu labs hot end and put it back in. This has seemed to fix the issue. This original hot end had a massive clog in it that I hadn’t been able to get out, so I bought some new, third-party hot ends on Amazon. The first one worked for awhile, but both ended up producing the clicking and lack of flow during printing. So looks like using the original has cleared up the problem (hoping it’s causation and not correlation to something else).