[bshambam]

Hey all,

I'm new to the n52 and I am overhauling the intake on my 09-e91.

There is a lot of oil coming out of the intake and the ccv system and i wanted to ask for advice.

Is this normal? I have never seen this much blow-by/oil consumption before.

Oil in the collector behind the TB


Oil on the Map Sensor


Oil from the runners dripping down


The Cylinder head and valves look really clean though.
Intake on Cylinder #04 for example:

[bluewater328]

Normal. Doesnt really matter because of the way it circulates it in the system. You notice that your valves are fine (esp compared to the direct inject N54 madness). What's lost there will never cause a "quart low" warning.

[The Nightman]

Mine had a lot of oil in it as well when I pulled it at 120k km. Intake valves were clean but the dealer used TerraClean at 100k km.

I would only worry about it if swapping to the 330i intake manifold where the excess oil can cause the DISA valve motors to fail

[F31B48]

Normal. I removed my manifold today and there was quite a bit in there.

[Biginboca]

Not many people know that bmw discovered lubricating the intake runners accelerates airflow lol

[bshambam]

I cleaned the intake manifold thrice *three times*

First time with Dish Soap and Hot Water
Second time with a Chemical Degreaser
Third time with Dish Soap and Hot water

All of the soap and cleaning solutions were rinsed off with a pressure washer and hot water.

I think it came out pretty well.



Intake Manifold runners w/o gasket

[E92William]

Looks great. The amount of oil depends largely on the condition your pcv system is in. It's not normal have a bunch of oil in your intake. When I took off my stock manifold there was almost no oil inside because I have a new valve cover. I did another guys car and it had much more as i believe it was the stock one. I guess it's not a big deal if your car doesn't have disa valves in the intake.

I clean mines with a brush and mothers trim cleaner

[bshambam]

I am overhauling the valve cover as well so I'll post that a bit later.

I am opting not to purchase a new valve cover for the sake of a diaphragm.
I have not heard any whistling so I will wait at a later time to replace the CCV mechanism.

[bluewater328]

Originally Posted by bshambam

I cleaned the intake manifold thrice *three times*

First time with Dish Soap and Hot Water
Second time with a Chemical Degreaser
Third time with Dish Soap and Hot water

All of the soap and cleaning solutions were rinsed off with a pressure washer and hot water.

I think it came out pretty well.


Intake Manifold runners w/o gasket

Originally Posted by E92William

Looks great. The amount of oil depends largely on the condition your pcv system is in. It's not normal have a bunch of oil in your intake. When I took off my stock manifold there was almost no oil inside because I have a new valve cover. I did another guys car and it had much more as i believe it was the stock one. I guess it's not a big deal if your car doesn't have disa valves in the intake.

I clean mines with a brush and mothers trim cleaner

Looks good, but honestly, you're overcleaning it for it to get dirty eventually.
I think for most, its just about time -- a better system will have less, but eventually you'll get some oil in there. And don't get me wrong, I clean them when I remove (most times) but generally, its just a good shoprag swab down.

[bshambam]

You're talking to my OCD self which is saying

' LA LA LA LA .... CAN'T HEAR YOU '

lmao. Yes, you are right! - 20 minutes after startup & its gonna be covered in oil all over again.

I guess this is because the car is new to my ownership, so, I like to give things the once over before I beat on it.

[The Nightman]

You could install an oil catch can, but it's another thing to service:

https://www.e90post.com/forums/showthread.php?t=1748288

[bshambam]

I am telling myself that I am not allowed to mod this car *engine wise* so I'll stick to oem as best as I can. It is a 10 year old car, so, I'll probably need to replace the Valve Cover soon. I hope that will reduce the Blow-by.

Installed a new Sensor


Cleaned and reinstalled the old MAP Sensor


Replaced the Hose that goes to the Valve Cover & Intake Runner Gaskets. She's ready to go back into the car!

[Volasko]

I had a ton of oil in my 3SIM when my oil separator failed and clogged. When it failed the vented air (after the oil was separated from it) is supposed to be directed back into the intake. When it fails oil ends up in the intake like you have seen. It was so bad for me I could hear a gulping noise from my intake manifold as it was sucking in so much oil. If you have everything opened up I would be swapping the separator too. I bet you this is your issue.

[Biginboca]

I would go one further and say if you have everything opened up and the intake manifold off then I would swap to a 3 stage manifold. No sense putting that 1 stage back on even though you did all that work cleaning it lol

[E92William]

What he said^^^^ lol. If you've spent this long with the manifold out then you probably don't rely on the car to daily drive so you have time to find a 3 stage to swap in and it's an oem upgrade too.