I have an Ender 3 Pro with BLTouch (original) and did at least a dozen of test prints to adjust everything (steps/mm, ...). I did everything at the target temp of PLA.
But I've still got the problem that if I print, my 1st (and possibly 2nd) layer print fine (i.e. good bed adhesion, first layer is almost perfect 0.2 mm high) with -2.575 mm Z-probe offset (
M851 Z-2.575) and for consecutive layers I need to reduce it to -2.435 mm to not have the nozzle drag inside the print. So there is a "step" of 0.14 mm.
I previously used the paper method to adjust the bed height as usual and followed the instructions widely available. I'm using Marlin 1.1.9 firmware (custom compiled, latest version of 1x-branch).
Any ideas what causes this issue and how to get rid of it?