Please help!!

[Burr]

I am trying to print ABS and I know the 3D printing lor is that there is no reason to use ABS but that's what I'm printing with and I would rather fix the printer than go out and buy new filament without fixing anything. Also, I built the printer it is not an off-the-shelf printer. It started life as an Anet A8 then it snowballed and I replaced it with all upgraded parts, new all-metal frame IGUS bearings, mosquito hot end (Chinese), BMG extruder (Chinese), BL touch probe (Chinese) glass bed with a 110 silicon heater PEI surface SKR 1.4 mainboard TMC 2209 drivers, marlin firmware, octoprint, superslicer, 24V supply. All the Gucci parts, only one problem it prints like crap and I have been trying for months to fix it with no luck.I print in a box for an enclosure for now I am trying to print parts for a nice-looking Ikea lac enclosure but I can't really print any usable parts. The problem seems to be inconsistent extrusion. But I have no idea what is causing it I have tried temperature calibration, first layer height calibration, extrusion multiplier test prints, e step calibration with digital calipers E steps are right on. I have swapped from a slim extruder stepper motor to a regular size one to make sure no missed steps, I have cleaned out the extruder and changed the nozzle a few times (0.4mm), used different slicers, different layer heights really everything I could think of and it still prints like garbage. I have no idea why I am getting inconsistent extrusions the extruder is mounted directly to the hot end and I even put a tiny piece of Capricorn tube in the small gap between. I can't think of any reason there would be any play or slop. I've checked the printer nothing seems loose. If you can recognize what I'm doing wrong by the prints or have things you think I could try please let me know.