T0 does not affect T3 in the same way. Just changed out all tension sliders to the very top right corner of the tinkered file (from the top middle for all of them), now I'm getting correct extrusion but this unintended movement.
I can also feel when T1 is selected, T2 is caught as well, and I can't move the filament etc. This is the only permutation that this happens with
edit: I replaced the T2 (extruder 3) tension slider with one with the normal bearing spacing, and the same spring tension (max at +2) . It is still reverse extruding T2 when extruding T1 (extruder 2). I can switch them all back to the same +2 tension and regular bearing spacing that they had before, but I was getting under extrusion problems with those sliders.
edit 2: replaced T1's slider to the previous one, it is still reverse extruding 100% of T1's movement with T2
Also when t1 is selected, t2 filament is tight enough between the gear and bearing that I can see the bearing move when I pull the filament in and out, and I hear the filament indentations scraping across the gear teeth.
edit 3: changed the sliders back to the top middle like they all were yesterday (with slight under extrusion oddities) and it took a second to adjust, but maybe it's working correctly now, starting the print rn will update.
edit 4: it's still happening with the old sliders I was just using yesterday. so confused!! surely the spring tension is not the culprit right?? just tightened the chassis bolts more than I normally do lets see if it happens again.
edit 5: It was the bolts! I noticed the extruder motor was getting pushed side to side a little and that it only happened sometimes with some transitions. my 3ec also had a nasty buzzing sound when homing but that has tightened up audibly as well. They need to more than just a little snug for sure, but not too tight still