Crazy under extrusion with Slic3r and Ender 3

Hi guys,

I've got an Ender 3 , mostly stock except the bed which i've changed to an Ikea Mirror . cut to size.

I've been trying Slic3r and ended up liking it more for how smooth top layers are printed with it, compared to CURA, although i have my cura settings on lock.

I dialed in Slic3r as well to the full extent but for some reason when prints are narrower than 5-6mm it starts under extruding to the point where i barely see the extruder motor spinning and it looks like it does in the picture i attached.

If i print it with Cura it comes out great. I've adjusted my steps/mm , adjusted extrusion / flow rate which was too high to begin with (had to go down to 89% ) , but slic3r is still driving me mad. Also both gcodes have M82 enabled.

I don't know what else to check at this point.