Oil pump solenoid leakage is a known issue. Should be covered under warranty, or maybe a recall by now? Oil leaks and wicks up the wiring harness, possibly damaging the "black box" or whatever. Mine was replaced under factory warranty. I would suggest getting it as CLOSE to stock (as far as engine goes), and go from there. This is not a new issue. Mods not affecting the oil pressure control solenoid should not matter at all.

 

This is what the solenoid leak looks like in its early stages...
Eventually the oil will start to drip off the pan on to your parking spot.
Pix taken from below and to the side from the passenger side.
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By the time mine looked like that, I was going into limp mode every few days.

 

For the N18 solenoid leak leak / wicking issues , see here:

https://www.northamericanmotoring.co...-check-it.html

thanks