Oil leak / sometimes smells of burnt oil - Valve cover gasket? (SOLVED)

[dukeofchen]

For future reference I just had an oil leak that from the bottom presented like the typical VCG or CPV leak, but my half moons were dry and CPV was replaced recently. It turned out to be the o-ring on the rear camshaft position sensor, which was dripping down to the oil pan / reinforcement plate and caked all over the O2 sensor wires. Even with an inspection mirror it wasn't immediately obvious where it was coming from.

19 years and 180k miles later, that thing had turned to a piece of hard black plastic, to the point where when I pulled the sensor I mistook it for part of the sensor itself and thought some idiot had re-installed it without an o-ring.

$2 for a replacement Uro brand o-ring from O'Reilly and good to go – in my impatience almost let the stealer get me for $11 on a part that probably costs two cents.

[Nate047]

I have this issue on my car currently, planning on addressing it with an OEM gasket soon. It has a VR gasket on it right now IIRC

[PSUEng]

I had this problem of leaking at the half moons on a VR gasket a shop put in. I replaced with a Genuine BMW, sealed the corners and moons per TIS and no problems since. If I recall, maybe back on M3Forum days, I remember reading that this leaking was due to 1) the packaging deforming the gasket (it was a shrink style package vs. OEM part comes in a cardboard box) and 2), the OEM BMW part material used by that supplier is unique to the OEM part. Whatever it is, OEM BMW gasket is the way to go here, and, probably everywhere for that matter.

EDIT: Anyone have a link to cam pos sensor DIY?

[Will]

This sucks. I have an Elring VCG sitting on my shelf. Seems like I should have went with the Victor Reinz or OE piece.

[Shonky]

+1 on Elring VCG leaking, switched to OEM and zero problems since

Same here. Elring only lasted about a year before leaking. I should have reused the genuine one that came off it. Although it was quite old and going a bit hard it wasn't leaking at the time. Went back to a brand new genuine and problem solved.

Elring might be OE or OEM or whatever but the Elring part most definitely is not the same as the genuine.

[ChapterM3]

I'm extremely curious as well - so far my OEM one is completely fine and cleared up the issue I was having. Funny to think that somehow an OEM supplier fails so early when comparison to the "genuine BMW" label version

[Slideways]

I wonder what the difference is between the original gasket and the VR or Elring gasket that makes it so much better? Is it geometry or something with the material?

I have a new Elring VCG someone gave me and I'm tempted to test it out. I'm fairly certain Elring makes all the metal style gaskets for the S54 - head gasket, VANOS gasket, timing cover gasket, etc. How can they not make a VCG that seals properly?

As one example of the Victor Reinz VCG, it keeps on sealing after 10+ years and multiple removal/reinstalls.

[zzyzx85]

I wonder what the difference is between the original gasket and the VR or Elring gasket that makes it so much better? Is it geometry or something with the material?

[cobra]

You can replace the cam sensor o-ring without removing the VC correct?

Yes. That's the first thing I replaced but the original looked fine.

[dukeofchen]

+1 on Elring VCG leaking, switched to OEM and zero problems since

[Cubieman]

You can replace the cam sensor o-ring without removing the VC correct?

[y2k_o__o]

I had the exact same leak last couple weeks when I start the car. Smokes coming from the engine bay like it has a blown engine
I took the belly pan out and saw brown oil dripping from the head all the way to the donut gasket flange.
Replaced with Elring valve cover gasket set without RTV, torque all the bolts in criss-cross sequence, and it solved the problem, and no more oil dripping.
Meanwhile, I also replaced the CPV seals.

Both could contribute to dripping oil to the header.

[Amos]

I had the same leak with a fresh Elring gasket a view years back, around the half moons and dripping on the exhaust. Replaced with OEM and no issues since.

[ChapterM3]

Just put my order in at FCP - they have everything Genuine BMW, just not in a kit like the Elring kit. Here they all are, with part numbers and quantities if you guys need them! I'm doing my spark plugs at the same time about 6k early but might as well while I have everything open.

Also a note to grab the cam sensor o-ring while you're at it - it's the only time you can replace it and it's around $1 so you might as well if you've not done it before. I already bought one previously that's why it's not in my order here but here's the part number if you need it:

BMW Position Sensor O-Ring
VNE-104482

[ChapterM3]

Wow no kidding - where has everyone been experiencing their leak from? Same location of the half moons in the rear?