Layer Height Issues

[pichuete]

hi guys , so after battling with so many issues my printer now is printing "Decent" but now im facing this layer gaps . it seems that layers have been " squeezed " to much . if i print lower than 3mm the problem seems to be worse .

im printing ABS and i have done several changes to my printer to make sure its not hardware related . also i have done several extruder calibration and test .

things i have done :

Replaced threaded rods
Replaced Extruder motor
Adjusted belt tension
Test different setting on Slic3r , Cura and S3D .
leveled the bed as good as i can using ABL topography.

so my question is . this layer gaps are common with ABS or im having Z axis issues? Skiping steps ?

at this point i really don't know what else to check . so any help will be appreciated .


heres some example including a temperature test that i did: