ADM, Flashforge’s automatic leveling and Z calibration system, measures the relationship between nozzle and bed through a pressure sensor under the plate. It’s accurate for the conditions it was run under, and those conditions don’t hold forever.
Rerun it whenever you move the printer to a new table, or even to a different spot on the same one, since a slightly less rigid surface changes how the bed sits under pressure. Do the same after swapping the PEI plate or changing the quick-release nozzle to a different diameter, both of which shift the exact nozzle-to-bed distance ADM is measuring. And if a first layer comes out patchy or uneven for no obvious reason, that’s a reasonable trigger too, before you start changing anything else.
Flow rate and pressure advance sit apart from ADM and are worth calibrating per filament rather than once for the whole printer. PLA, PETG, TPU and the CF-reinforced filaments all extrude differently, and a value that looks right on PLA can leave PETG under or over extruded.
Change one variable at a time. If you adjust flow, print a test and look at the result before touching pressure advance too, and avoid retesting with a different filament in the same pass. Stacking changes makes it hard to tell afterward which one actually fixed, or broke, anything.
Keep a rough note of what you changed and on which filament, even just a line in a notes app. FlashPrint 5, Orca-Flashforge and Orca Slicer all store per-filament profiles, so once a setting is dialed in for a given spool, it’s worth saving rather than re-guessing it next time.
If print quality drifts after weeks of otherwise normal use, ADM and a fresh flow check are the two places to start, in that order, before assuming something mechanical has failed.
These routines map onto broader calibration practice too. The general guide to 3D printer calibration steps in the right order puts ADM leveling and flow tuning in context alongside everything else, and the wider rundown on leveling a 3D printer bed explains why an automatic system still depends on a clean plate. Pair calibration with a look at the Adventurer 5M maintenance schedule so a dirty plate or sensor doesn’t get mistaken for a calibration problem.