[dreadedN43]

Hi all, this forum has been of great help for me, thought I'd share something as a thanks.
This isn't much of a step-by-step, but I hope it's helpful nonetheless.

Some context:
e91 320i 2008/09 n43b20a, ~320000km (if the dash is to be trusted )

I had the red oil pressure warning appear 3 times this year:
* Long drive, gave it some good gas when overtaking, seconds later the car went into what felt like limp mode, the gas pedal made barely any difference, and soon the warning light popped up.
* Long drive, no aggressive driving, came to a stop at a gas station, the warning popped up.
* Shorter drive than the previous two, more aggressive driving than usual, slowed down looking for a parking spot, the warning popped up.

Stopping and starting the engine cleared the warning, leaving no codes.
Although the 30C1 "DME: Engine oil pressure control, static" code did appear occasionally. Can't confirm if it's correlated to the red oil pressure warning though.

The theme seems to be long drives/high engine load and coming to a stop afterwards.
Googling for what the issue could be:
* Oil pressure control valve
* Timing chain guide pieces blocking the oil pickup
* whatever the hell else

I'll have to check the oil sump with a borescope camera the next time I do an oil change, so for now I ordered the oil pressure control valve.


But I was hesitant to replace it myself:
This tutorial, and some online posts warn about the valve snapping off as you're trying to pull it out (which happens in the video):

And I don't have the tools to deal with that.

Also, an interesting video from the same channel about how the sump might cause this issue:

As I was driving to pick the part up, the third red warning light popped up, and I decided to do it myself immediately.
I followed this tutorial to get to the valve.

I doused it with tons of some random penetrating oil, rotated it the slightest bit, more penetrating oil, tried carefully pulling it out, nothing.
So I decided to give it one final dose of penetrating oil and leave it overnight.

Then I saw this german tutorial which made pulling the valve out look real easy.

The next morning, it looked like there was the slightest opening between the valve and the engine block.
Not sure if that's from the penetrating oil, my previous attempt or the stupid idea to work on a hot engine last night.
Doused more oil on it, took some pliers, and pulled on it while carefully twisting the valve the slightest bit



and it popped out all in one piece!




Replaced it with the new one (VEMO), drove around giving it more gas than usual, so far so good. Of course, it's still too early to tell if this helped.
Update about a month after: no oil pressure issues! Looks like the bad part was the problem.

Seeing how bad the valve is, I also ended up pulling out the vanos solenoids, some black spots, but not as bad. Cleaned them up with some electric parts cleaner.