An oil pump replacement success, and some reflection.
Hi all. We have a 2020 M340i xDrive in the family, 3/19 build, super early car! Non-ZTK. For a long time oil measurement would fail unless it was jusssssssstttttt up to temp or cooled up 15 minutes. 0W-20 or 0W-30 didn't matter. Finally had it taken care of a few weeks ago to the tune of an $8600 Geico mechanical breakdown claim ($250 out of pocket!, also needed the transfer case crossmember thing fixed due to a leaking bushing). Never had any warning lights, oil pressure was always great when driving and WOT, but there was sometimes a code for high oil pressure in info memory on BimmerLink.
Before we took it in, I decided to really look into what was happening. You could actually see what was causing the oil measurement to fail, the oil pressure being all over the place. Oil pressure MUST stay around 44-45 psi average during the measurement or it will fail. Now on the new oil pump, regardless of oil temp (0W-20 at first, I just changed back to 0W-30), it does, and succeeds. Prior to this, it would hover around 44 psi when just up to temp, and jump around to 47-48 psi when hot! As you know, oil pressure goes down as heat goes up, as oil thins out, yet clearly the opposite was happening here. I've seen pictures of the internals all damaged and cracks and in pieces, scary stuff, I suspect that piece that fails is what regulates oil pressure, feel free to correct me!
Get this taken care of before you get a CEL or lose an engine! Any ZTK package car is safe from this, and anything 2022MY non ZTK or ZTK and onwards apparently. My dealer was super knowledgable and knew exactly what to do, no issues or haggling.