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Crankcase ventilation: leakage P04FC/16050A

ruskimafios

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I've posted this on Reddit and Bimmerpost but can't get any traction. Hoping MKV 3.0 owners can chime in.

I have a 2022 M340i which I recently purchased from an auction. Vehicle is stock as far as I can tell. 38k miles on the odometer. Check engine light since day one. No smoke out the tail pipes, no rough idle or noticeable performance issues.

Crankcase Ventilation: Leakage
Fault Code: 16050A
SAE Fault Code: P04FC
I've followed the ISTA action plan and here's what I've done so far:

Visually inspected both crankcase vent tubes from valve cover and engine block - they're not broken or cracked

Performed smoke test - zero leaks

Replaced oil cap(opened cap while engine was on, don't feel any excess pressure pulling on it)

Inspected intake tube into the turbo- basically no oil in the intake inlet to the turbo.


The last thing that I can think of trying is replacing the valve cover since the PCV is built-in and cannot be serviced.

Before I proceed with that, is there anything else I can try or look at? Any sensors? What if the DME was FEMTO unlocked by the previous owner but never tuned(they didn't have the vehicle for long based on sales history). Unfortunately, I don't know who the previous owner was. Is there an easy way to check if it's unlocked?

Maybe DME needs a software update? Anyways, appreciate any and all help in advance. Thanks!
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Supraman40

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You can check if your DME is unlocked, but not sure why that would cause the error. Is everything connected correctly to the intake?
 

Thraxbert

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Exactly how was the smoke test done? What orifices were plugged?
 
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ruskimafios

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Exactly how was the smoke test done? What orifices were plugged?
By disconnecting the air intake from the intake box and plugging it there with an inflatable plug. Then sending smoke through that. I also did a vacuum test with a manometer and got 0mbar of pressure. Same exact test on my buddies 2024 read -10mbar(within BMW spec at idle).
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