2011 335I oil from O2 sensor

[Mdlrat]

Why am I getting oil from my O2 sensor on down pipe? Sometimes it does and sometimes it doesn’t and seem to bubble from around the threads. I haven’t tried to tighten yet but wife thinks motor is gonna blow. No indications or malfunctions but it’s smokes

[bmwdirtracer]

Wow.

Well, I was about to tell you that the O2 sensor's not screwed in tightly, and that you might have valve guide / seal problems.....

....but then, I thought....let's simplify what you're seeing, to something more logical.

I'd suggest that your valvecover gasket is leaking ( a hugely common issue), and dripping onto the exhaust in the vicinity of the O2 sensor. There is probably oil in the spark plug wells; I'd recommend you do the VCG and Spark plugs a the same time. (They are 50,000 mile maintenance items on your engine anyway.)

VCG is a 6.5 hour job on your engine; spark plugs will add another half hour I expect.

[Mdlrat]

Ok thanks for the info. I’ve tried looking with a mirror but everything is crammed in so tight it’s hard to see. May as well do the oil pump gasket as it has a small leak also. The oil dripping on the downpipe smokes and smells bad and the wife thinks the motor is gonna blow

[dworthy]

I bet if you run you hand on the passanger side of the motor, you will find oil. The engine will not blow up because it is leaking a bit of oil, smoke, yes, but not blow up.

The other gasket that likes to leak on that motor is the oil filter housing gasket, I am not sure why you are saying oil pump gasket.

[bmwdirtracer]

Since you mentioned the oil filter housing gasket (by the wrong name), there are a couple of things you need to know. First, the "book time" on this item is 4.6 hours, plus likely another 1/2 hour for the oil cooler gasket, which you should absolutely do at the same time. There are a couple of tricks, which require very specific tools, which can determine whether you can do this job in either ~ 5-6 hours, or 2 hours.

If you're having a shop do these jobs, make very sure it's a BMW / Euro specialist shop. If you're doing these jobs yourself, you will save a ton of money, but both jobs really require significant experience to avoid breaking things, or having to go back and do the job again.

[pbonsalb]

What is the special tool and trick to do the oil filter housing and cooler gaskets in 2 hours?

[bmwdirtracer]

Just for you, my friend:

You need a 1/4 drive E10 universal socket from one of the tool trucks. a regular E10 with a separate u-joint won't work. This MUST be 1/4 drive!
You also need an E10 ratcheting gear wrench.

First, you remove all the intake manifold top bolts, which hold the manifold to the cylinder head. There's about 7 of them, all 11mm. (Don't drop them) (Actually, 2 are bolts, 5 are nuts)
Next, you pull the manifold back about an inch. And voila: now your E10 universal 1/4 drive socket, on a 6" or 8" extension, can just wiggle onto the innermost bolt of the oil filter housing, past the very intrusive manifold runner.
Then, you remove the oil cooler unit from the oil filter housing (3 E12 bolts), tie it back out of the way. (You now have oil and coolant everywhere, of course.)
Now, you remove the easy, topmost bolt from the oil filter housing.

Now, you use the E10 gear wrench (ratcheting box end) to begin undoing the remaining oil filter housing bolt. Here, the important trick is to keep pulling the oil filter housing backwards, away from the head, as you undo this bolt, so that you don't run out of room, and have to unbolt the plastic flange for the coolant hose which runs down to the thermostat. BEWARE: this flange will break, if you undo those 2 bolts and remove it !

There you are: the housing is in your hands, and all you have to do is clean all the gasket areas thoroughly, make sure there's no pieces of the old gaskets in the grooves, and put it back together.

Of course, it's a good idea to do your oil change now....... that's not included in the 2 hours.

[bmwdirtracer]

Took me a while to find one:
https://store.snapon.com/Universal-T...0-P642960.aspx

Yes, of course it's ridiculously expensive.

Here's the other one:

https://www.amazon.com/GearWrench-92.../dp/B000HBF5LQ

[pbonsalb]

Those are specialized Torx tools but not pulling the intake mani would be a timesaver. I knew it would be a pain so I combine the filter housing gasket with a de-goo and de-carbon of the intake chambers since I did not want to pull the manifold twice.

[Mdlrat]

I don’t know why I said oil pump I meant oil filter housing yes

- - - Updated - - -

I have a friend that is European car certified is going to do the work for me much cheaper than the dealership he has all the tools and diagnostic equipment

[pbonsalb]

If you have never done the carbon blast and scrape, you should. I could not believe the amount of goo in the chambers. Car runs better.

[Mdlrat]

Changed VCG oil filter housing gasket and plugs $600

[bmwdirtracer]

Wow, I don't know where you went for those services, but I'm amazed. At any pro shop I know, you'd pay "book time", which is from either Alldata or Mitchell -- and the cost would be twice that amount, for labor alone.

[Mdlrat]

Son of a friend of mine at work works at a euro shop and does stuff on the side. I may give him a little more cause I know what BMW shop would charge. His son is very knowledgeable on BMW Audi VW

[pbonsalb]

$75 an hour tax free no overhead is pretty good earnings. Everyone is happy but the government.

[Mdlrat]

And that price was including parts

[bmwdirtracer]

$75 an hour tax free no overhead is pretty good earnings. Everyone is happy but the government.

Okay, maybe I need to reconsider doing sidework.

Don't much like the government....I'm just going to leave it at that, because this is a mechanical forum.

[02Pilot]

Don't much like the government....

I knew I liked you, Chris.

Oh, and in your present locale, I believe the preferred terms are "revenuers" or "gubmint".

[bmwdirtracer]

Previous locales include Maui (~17 years). Connecticut. NYC. West remote Texas. Tennessee mountains for high school, London England for 7 years. Nairobi, Asuncion, Sydney, LA, SF, Orlando, and yeah, more.

Politically, yes, well, I don't much like the government. You want more than that? We'd likely have to go to that other forum, where I pretty much hate everybody.

[WadiM3]

We're is this other special forum hahaha

[02Pilot]

Nope, don't want or need more. Aside from expressing a universal distaste for humans who organize for the express purpose of exerting power over and controlling other humans, I don't discuss politics outside of a few specific circumstances: over a friendly beer, when contractually obligated to do so, and when I want to piss off certain extended family members at holidays.

[Mdlrat]

$200 in parts and $700 labor, he asked for less but it thought it was too little for the work knowing what BMW would charge

[bmwdirtracer]

That was a very wise decision, Mdlrat. As a pro tech who really hasn't done more than a tiny bit of side-work in the last ~8 or 10 years, I would have greatly appreciated that extra consideration.


Oops, O2 pilot, I'm sorry. I went back and deleted part of my post # 19, because my "political leanings" were perhaps a bit too obvious, for this non-political forum. I too generally try to avoid expressing my political views in public. Sometimes it just slips out.