Help - N52 oil leak around oil filter housing?

[Texan Engineer]

All, looking for some help or tips as to where my oil leak might be coming from.

Car is a 2013 128i with the N52K motor, 16k miles on it. I've put the car into semi-storage for the winter since November, running either for 30 minutes or (when possible) doing a brisk 10+ mile drive for about the same amount of time. The last run was about three weeks ago, just 30 minutes of idling followed by a slow roll around the block. No oil was noticed last I cleaned the engine bay about 4-5 months ago, and there never have been leaks anywhere.

Today I went to check on it and found a small, very shallow puddle of oil on the garage floor. Opening the hood, I found a light spray of oil centering around the oil filter housing that extends slightly further around the engine cover but NONE on the underside of the hood itself. See the attached picture.

I also noticed that there's some sort of open threaded hole (circled) near the oil filter - am I missing something? I don't think it's the oil filter housing gasket, since the car is so young and the faying surface around the oil filter housing does not have a single drop of spilled oil. I also found a bit of oil leakage collected on some of the horizontal surfaces of the engine block just below the intake manifold - can't take a picture but it would be literally below the runners of the intake if you looked directly down through the gaps of the intake manifold and see bits of engine.

Does anyone have any tips or suggestions on where to start looking?

[NorthernDancer]

Can't help a lot but can say this:
-because of the spray pattern, its being pushed out from somewhere where there is high pressure which might eliminate valve cover.
-the two green dots (oil filter cap & body of engine) should normally be aligned but they are not too far off so someone has not over tightened it.
-for storage, never start car just to let it idle; if you can't drive it for 15 minutes or so, don't start it. In the frozen North here, we store our cars for 5 months, never starting them (but batteries either removed or put on maintenance chargers)
-hopefully no "corner car garage" has been working on car.
-I've heard oil filter housing gasket can fail-not normally at such low mileage
-take car to BMW dealer (you're still under warranty?)

[BrokenVert]

Well the oil filter housing gaskets on these cars are prone to leaking, but ive never heard of one happening that soon.

[Texan Engineer]

yea, i'm aware of the oil filter housing gasket but this definitely doesn't look like it. the oil filter housing gasket went on the parent's e91 and it looks like the typical slow seepage around the housing itself (same as what you find on google) - not the the light spray i'm getting.

i plan to retorque the oil filter cap myself just to check, but like NorthernDancer said, the previous mechanic (local BMW dealer) probably didn't significantly overtorque. since it is still under warranty, i probably will have to just throw it to the dealer and let them figure it out. i was just hoping for some better insight before i went in.

[bmw1racer]

Considering the spray pattern in relation to the oil filter cover, it appears that the gasket in the cover is leaking... Maybe remove the cover, check, and re-tighten?

[NorthernDancer]

Further to what bmw1racer is saying, if memory serves me correctly, it is quite easy to put the big "O" ring for this cover in the wrong groove.

[MightyMouseTech]

Looks like oil filter cap seal is leaking. Also, that "hole" you have pictured is normal, should not be anything in there.

Also, really bad idea to let your car idle like that and not get it up to temp. You are making lots of water from combustion and it is just going into your oil, and filling the exhaust. Either drive it till the oil is warmed up, or do not start it at all. You are doing much more damage than good.

[Texan Engineer]

yea, i will check the oil filter gasket once it warms up a bit again. i find it odd that it would only start now though - the last oil change was in july and it hasn't sprayed like this before.

if that doesn't fix it, it'll go to the dealer most likely

[NorthernDancer]

and just to be more accurate, we're talking the very large "O" ring in the oil filter cap.

[Texan Engineer]

yep i know which o-ring, changed out the oil a few times on these engines already. unfortunately, it's freezing where i'm at and my garage has no heat...i'll report back eventually...

[all4bspinnin]

My 09 n54 oil cooler/filter housing o rings were leaking and oil was seeping down the front of the engine. That may be similar to what your car is doing.

I replaced all of them and cleaned the front of the engine. Looks like new now and no issues with leaks. Its not hard to replace the O-rings. You could start there.

Also, when was the last time you changed the oil?

[Texan Engineer]

Got it back from the dealer yesterday, and it's not leaking anymore (so far). Per their assessment, they say it's caused by flipping the oil filter cap upside down...

So apparently, if you flip it upside down (when you're changing your own oil, for example), oil can drain into an "area that is not sealed by the o-ring". Once this happens, the system pressure will push it out. This sounds a bit strange to me, but apparently it even has a TIS (TSB?) associated with - the SA showed me. I was also told that the o-rings looked fine, and that was not the issue.

Regardless, problem seems fixed. Try not to flip the oil filter caps upside down I guess? (and the last one wasn't me - that would be the good old dealer...)