[l8nit3]

Vehicle: E90 328i Xdrive 2011
VIN: NN85977
KM: 164500
Issue: nasty substance found when adding oil
Potential cause: blown head gasket

Quite simply, I had a bad smell (turned out to be locked up ebrake) but did a quick oil level check to see if it may be burning.

Saw it was almost exactly in the middle of the small display, so decided to add the small amount I keep around on hand. Keep in mind, I use liqui-moly and it's meant to be green.

Any thoughts or suggestions on what this may be , although I assume head gasket.

If that's the only possible cause, any suggestions at DIY fixing or a solid indy in niagara region (ontario) would be incredibly helpful.

Just changed (proactive) thermostat and a dead water pump (not sure if this could have an effect), and was getting ready to do VCG and oil filter housing gasket aswell as vanos solenoids (pre-emptive, high milage).

[whyzee125]

Good news is, it's highly doubtful you have a bad head gasket. I see you're about to do your OFHG, so unless that's preventative, a leaking OFHG CAN contaminate your oil with coolant. A bad PCV can also cause this and if your valve cover is original, it's probably due. Lastly, if you make a lot of short trips without warming the car up to temp all the way, this is also normal. You need to run it at temp for about an hour to cook off any condensation inside your engine or it will look like this--it's a small amount assuming no other issues though so it really isn't anything to worry about if you've ruled out a hardware issue. Just get it up to temp and burn it off. But between these 3 things, you likely have a hardware issue, just not a head gaskset. Which is good news!

[l8nit3]

Originally Posted by whyzee125

Good news is, it's highly doubtful you have a bad head gasket. I see you're about to do your OFHG, so unless that's preventative, a leaking OFHG CAN contaminate your oil with coolant. A bad PCV can also cause this and if your valve cover is original, it's probably due. Lastly, if you make a lot of short trips without warming the car up to temp all the way, this is also normal. You need to run it at temp for about an hour to cook off any condensation inside your engine or it will look like this—it's a small amount assuming no other issues though so it really isn't anything to worry about if you've ruled out a hardware issue. Just get it up to temp and burn it off. But between these 3 things, you likely have a hardware issue, just not a head gaskset. Which is good news!

Firstly, thank you for taking the time to reply.

Yes, I do believe the OFHG is leaking a bit, either it or the VCG, which is why I was simply going to replace both.

My daily drive during the week is about 12km each way to and from work. I do one 180km drive round trip every Sunday.

9/10 times I allow the revs to drop to ~600-700 before driving to allow the engine to warm first, not quite sure if that's long enough to be at temp though.

Now, for the suggestion of burning off the excess moisture, I assume that would be after fixing the gaskets and changing the oil ASAP?

How can I determine for sure (or reasonably sure) which of the 3 issues it's likely to be? OFGH, PCV, or the dreaded head gasket? Or would it just be smarter to replace both , do an oil change, and drive for a short while to see if the issue persists?

I'm quite new a diagnosis, but am a very quick learner.

[POBEP]

Originally Posted by l8nit3

Firstly, thank you for taking the time to reply.

Yes, I do believe the OFHG is leaking a bit, either it or the VCG, which is why I was simply going to replace both.

My daily drive during the week is about 12km each way to and from work. I do one 180km drive round trip every Sunday.

9/10 times I allow the revs to drop to ~600-700 before driving to allow the engine to warm first, not quite sure if that's long enough to be at temp though.

Now, for the suggestion of burning off the excess moisture, I assume that would be after fixing the gaskets and changing the oil ASAP?

How can I determine for sure (or reasonably sure) which of the 3 issues it's likely to be? OFGH, PCV, or the dreaded head gasket? I'm quite new a diagnosis, but am a very quick learner.

Start with OFHG, do not forget mickey mouse hose billet.
It will highly likely fix the oil moisture.

[l8nit3]

Originally Posted by POBEP

Start with OFHG, do not forget mickey mouse hose billet.
It will highly likely fix the oil moisture.

So change the OFHG, change the oil, and then check periodically to see if I'm getting the same issue?
If not, profit. If so, on to the next?

Is there any definitive or semi-definitive test I can do once the OFHG is changed to rule out PCV or head gasket before allowing the oil to become contaminated again? Just hoping to avoid any further damage if possible.

[whyzee125]

Originally Posted by l8nit3

So change the OFHG, change the oil, and then check periodically to see if I'm getting the same issue?
If not, profit. If so, on to the next?

Is there any definitive or semi-definitive test I can do once the OFHG is changed to rule out PCV or head gasket before allowing the oil to become contaminated again? Just hoping to avoid any further damage if possible.

Start by taking it for at least an hour drive and check the cap after that. It will likely be reduced. OFHG is a serious issue and should be dealt with asap. Only use genuine bmw gaskets for this and not el ring, victor reinz, etc. Once you know that’s not leaking then keep an eye on it. I always change coolant and oil at the same time as OFHG but May need to flush your coolant one more time if it’s contaminated.

Difinitive tests could be:
block tester (tests your cooling system for exhaust fumes)
Used oil analysis (can determine if you are getting any coolant in the oil)

[l8nit3]

OFHG was luckily already on its way anyways, with an oil service kit from ECS. So will do both, and a coolant flush the moment it comes in.

Should it come to the PCV , on the 2011 E90 N52, is is actually a part of the valve cover? Or is it replaceable separately? I've seen online tutorials for both and can't seem to get a solid answer.

<edit>
I also have an error code for oil condition sensor (0x2E9F), which makes a lot more sense now. Is it possible to clean the sensor, or should it just be replaced when doing the oil change?

[whyzee125]

Originally Posted by l8nit3

OFHG was luckily already on its way anyways, with an oil service kit from ECS. So will do both, and a coolant flush the moment it comes in.

Should it come to the PCV , on the 2011 E90 N52, is is actually a part of the valve cover? Or is it replaceable separately? I've seen online tutorials for both and can't seem to get a solid answer.

<edit>
I also have an error code for oil condition sensor (0x2E9F), which makes a lot more sense now. Is it possible to clean the sensor, or should it just be replaced when doing the oil change?

I would replace the sensor as it's cheap and even comes with some of the kits for the N54. Not sure on the PCV as I've never had an N52, sorry about that!

[l8nit3]

Originally Posted by whyzee125

I would replace the sensor as it's cheap and even comes with some of the kits for the N54. Not sure on the PCV as I've never had an N52, sorry about that!

Wonderful, thank you for the information and for taking the time.

The gasket, and oil service kit are on their way, and as soon as I rectify my initial issue (stuck ebrake) I'll be going for the ~1 hour drive and see if it helps clear up some of the moisture.

Is there an at home method of verifying whether it's simply moisture from short drives not at temp, or whether there has acryally been a coolant contamination? (Changing the gaskets either way), or is it simply sending it away for analysis?

[FimbulWinter]

Originally Posted by l8nit3

OFHG was luckily already on its way anyways, with an oil service kit from ECS. So will do both, and a coolant flush the moment it comes in.

Should it come to the PCV , on the 2011 E90 N52, is is actually a part of the valve cover? Or is it replaceable separately? I've seen online tutorials for both and can't seem to get a solid answer.

<edit>
I also have an error code for oil condition sensor (0x2E9F), which makes a lot more sense now. Is it possible to clean the sensor, or should it just be replaced when doing the oil change?

There is repair kit for the pcv only. However I would change the entire valve cover instead of just replacing the pcv if your valve cover is still original

[l8nit3]

Originally Posted by FimbulWinter

There is repair kit for the pcv only. However I would change the entire valve cover instead of just replacing the pcv if your valve cover is still original

Awesome, Thank you for the information.

If the OFHG doesn't resolve the issue , I'll take your advice and definitely just do the entire valve cover.

May aswell do it right, once. 🙂

[tcphoto]

You need an Italian tuneup, drive it till the engine gets up to temperature to burn off the condensation, it builds up when you make short trips and the engine doesn't get up to operating temperature.