[MrSeabass]

Posted this on another forum and got zero traction for it, retrying here.

Long story short, my 127K mile 2013 35i developed the dreaded 'failed PCV howling' issue three weeks ago. However, I replaced the PCV valve by carefully removing the old one - which was not damaged when I examined it - and it remains. Here is a video of how it currently sounds at idle, cold/normal operating temperatures with the AC off: https://streamable.com/hiurl0. You can hear the sound jump between two pitches.

I did not detect/feel/find leaks in any of the tubing coming off the valve cover and the intake, but I could be mistaken. Valve cover itself has a gasket that I replaced around 80K miles. The squealing stops when the RPMs hit about 2K and don't come back until the RPMs go below 1.5K roughly. The sounds generally 'chirp' with the AC off like in the video, and is more steady and solid with the AC on. Have not noticed any other details besides a persistent P0171 error, and the car no longer goes into ASS mode. Outside of the valve cover and oil filter housing gaskets being replaced, there has never been any issue directly related to the engine/idle before. I did not remove the valve cover and inspect it as I do not have a set of 'may as well replace them' valve cover gaskets on hand if/when I do.

I'm one step away from taking the car to a dealer to diagnose where it's coming from, but thought I'd ask the folks here if they had a similar not-the-PCV howling happen to them. I've been fortunate enough to DIY everything to my car since I bought it 5 years ago, and I'd rather not end that streak. Thanks!

[MrSeabass]

So I take it nobody else has had this problem before...

[Bdavi011]

I honestly think it is the whole valve cover. Others have attempted to just replace the pcv instead of replacing the whole valve cover but the problem persisted. I believe everyone who eventually just replaced the valve cover ended up getting the issue fixed. Maybe someone else who has experienced the same issue can chime in.

[MrSeabass]

Went ahead and brought it by the dealer, they said just replace the valve cover in its entirety, so I will.

[evilchargerfan]

From what I read, the valve cover has more than 1 diaphragm. For some lucky owners, replacing the Pcv with a $15-$20 one, may solve the issue.

I was successful and repaired my issue by doing just the Pcv

(I do have a new Valve Cover is on deck, for if/when the Pcv fix eventually fails)

PCV:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Valve Cover:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[evilchargerfan]

I follow steps this guy did:
https://f30.bimmerpost.com/forums/sh....php?t=1758775

Biggest take away was to not over do the adhesive and not allow it to go inside




I noticed alot of others on youtube would use an excessive amount of adhesive, and they would apply inside the PCV itself, I have a feeling that over flows into areas it is not supposed to

(illustrated by a poorly drawn red circle)

[Bdavi011]

Let us know if the new valve cover fixed the issue

[MrSeabass]

Yayyyy, just spent 4 hours swapping out a valve cover I got off of Amazon: https://www.amazon.com/dp/B07YFXKKN1 and https://www.amazon.com/dp/B07SZJ8ZLN

Car is 100% back to normal, so I can only assume something internal to the cover other than the PCV failed.




Oh and a bonus - here's what the dealer wanted to charge when i asked them to look into it:

[evilchargerfan]

glad to hear you're all set