[theworacle]

My 328is currently has about 83k miles on it. When fixing an oil leak, I noticed some build-up in the engine compartment (see photos). My mechanic said this was due to a PCV, which is supposed to pull out excess water out of the engine compartment.

I live in Minnesota and at the moment, is very cold here. I imagine the insulation on the PCV isn't enough to perform well in cold weather. I didn't even want to touch it because it seemed brittle. The build-up seems to be because the water isn't being evacuated properly. Mechanic told me that BMW came out with a newer version of this PCV which has a foam insulation.

My questions:

• Does the build up look serious?
• Are you aware of a replacement PCV that will do a better job of extracting moisture?
• Is there any way to clean out this build-up in the compartment? Or should I assume that a new PCV will clean this over time?

Thank you in advance!

 

[ZeGerman]

What are your driving habits? How many miles each day?

 

[theworacle]

Pretty conservative driver. In cold weather, I idle for 30 seconds before moving out, drive in low gears at 3000rpm for about 5 min before getting on freeway. Usually cruise around the speed limit on the freeway. Don't drive it for super short trips, but have done so on rare occasions.

Car is driven 3 days in the week. Average distance of 18 miles per day.

 

[ZeGerman]

Hmmm, you're doing everything right with regard to driving habits, so the sludge buildup is not due to how the car is being used, which means that something else is not working correctly.

It could be due to a clogged oil separator line, or it could be something more serious. I would not feel comfortable with that amount of moisture mixing in with the oil if it were my car. It can be hard on everything, including bearings, etc. First thing I would do would be to check the coolant just to make sure there isn't any oil contamination in the coolant (suggesting a failed head gasket, which also yields these symptoms).

As far as removing the sludge goes, many people have very high praise for Sea Foam, although I have not used it personally.

http://www.seafoamsales.com/

 

[B1MM3R]

Just make sure your oil is not milk shake like...I would drain it out and make sure...my fiance's x5 is doing this in the winter and dealership said that was normal on the e53 3.0...have not heard much about that on e36's tho. If not losing and coolant and they are not mixing then you are safe from major damage, but I would look into the oil seperator like karl said.

 

[dc_wright]

18 miles a day 3 times a week is pretty short mileage in cold weather. The area around the oil cap has a baffle under it and gets the worst air circulation in the top of the engine. That look like typical condensation residue to me......

 

[theworacle]

Thanks for all your advice. I'll be sure to update this thread with my end result.

 

[RhymeGrime]

I would 2nd SeaFoam, I use it every other oil change, sometimes every oil change. I definitely noticed the oil draining out to be blacker than usual the first few times I used the seafoam, it's still pretty dark coming out but not as dark as it used to be.

 

[drivinfaster]

18 miles a day 3 times a week is pretty short mileage in cold weather. The area around the oil cap has a baffle under it and gets the worst air circulation in the top of the engine. That look like typical condensation residue to me......

this...

bmw doesn't use a pcv valve in the sense that most people are aware of, but they do have a cranck ventilation system. i've never seen one clogged, though...:dunno:

take the thing out for some long road blasts, wind her up and let he go!! :roundel:

df

 

[B1MM3R]

If you do less driving then you should do a little bit more of that driving "spiritly"...thats what I do to get the engine to run all the moisture out..

 

[granlund]

The yellow sludge is, as pointed out, caused by moisture in the oil which will freeze and can cause problems.

It takes significantly longer for the oil to heat up than the coolant indicated on the dash. In the winter, I would recommend at least a 30 minute highway drive to make sure the oil is properly warmed up for the moisture to disappear.

 

[max911]

In cold weather, I idle for 30 seconds before moving out, drive in low gears at 3000rpm for about 5 min before getting on freeway. Usually cruise around the speed limit on the freeway. Don't drive it for super short trips, but have done so on rare occasions.

Car is driven 3 days in the week. Average distance of 18 miles per day.

Being cold weather experienced, if I were you I'd let the car idle for a lot longer than 30 seconds. In fact, let it idle for about five minutes or whatever it takes for the engine to get up to operating temperature. On an 18 mile commute, the engine is not getting warm enough for the oil to get hot enough to get rid of the H2O. And remember, it takes the oil a lot longer to get up to operating temperature than the coolant does.
I'd get the engine coolant and oil get as warm as possible, then drop the oil / filter and replace with new. That would get rid of some of the water still contaminating the oil.

good luck,

max

 

[theworacle]

The only reason I stuck to the 30 second idle is because the BMW Manual recommended this, followed by a slow drive to warm up the engine. Their theory is that idling for too long causes more harm than good. Quite a few theories out there...trying to find the best one.

 

[ZeGerman]

Being cold weather experienced, if I were you I'd let the car idle for a lot longer than 30 seconds. In fact, let it idle for about five minutes or whatever it takes for the engine to get up to operating temperature. On an 18 mile commute, the engine is not getting warm enough for the oil to get hot enough to get rid of the H2O. And remember, it takes the oil a lot longer to get up to operating temperature than the coolant does.
I'd get the engine coolant and oil get as warm as possible, then drop the oil / filter and replace with new. That would get rid of some of the water still contaminating the oil.

good luck,

max

This is wrong, wrong, wrong, and will actually contribute to additional engine sludge. You want to start the car, let the idle settle a bit (30 seconds to 1 minute should be fine in cold weather) and start driving. The engine will be brought up to temperature faster (which is what you want) if you drive the car, not idle it. This is why remote starters, and the act of letting your car idle to temp in the mornings, are known for being bad for your engine.

 

[max911]

i don't want to get into an argument Mr. ZeGerman.
But, have you seen the temperatures in MN the last while ??

If you start driving with a cold engine, and only go 18 miles ,,, with zub zero Fº temperatures flowing through the rad and the bottom side of the engine, the oil is NOT going to get up to operating temperature in that short of time.

I know about the consequences of prolonged idling.
I also have a few decades of experience with cars and trucks in very cold weather.
When the temps are very cold, letting the engine get on its way up to temp before for blasting through the cold air accelerates warm up.

I wonder if the original poster's thermostat is functioning properly ?? If it was not closing fully to let the coolant get to full temp - that could be a contributing factor as well

 

[jonesin]

http://www.abc.net.au/science/articles/2007/09/27/2044311.htm

http://www.popularmechanics.com/cars/how-to/4213313

http://www.1addicts.com/forums/showthread.php?t=304261

And if none of those happen to float your boat:

That screenshot is taken directly from the E36 Owners' Manual.

 

[granlund]

The advice against warming up of the engine via idle is partially due to emissions. An idling engine can easily take 15-20 minutes to light up the cats in the winter. Driving off immediately (of course without full throttle accelerations) quickly speeds up the process of getting to closed-loop combustion.

My own rule of winter starting is to idle for as long as it takes to scrape the windows.

 

[jonesin]

I tend to brush off any snow, then only start her up before I scrape the windows. ~2 minutes of idling that way.