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Yellow Sludge in Oil Separator pipes!!!!!!

8.9K views 35 replies 9 participants last post by  jfoj  
#1 ·
So my oil separator pipes have yellow sludge build up inside them as well as trace amounts under the oil cap. Is it safe to drive for 2 weeks like this while i wait on the replacement parts ? And is there any thing i can do right now while i wait? thx!:banghead::banghead::banghead:
 
#10 ·
You really need to verify that the engine is working at the proper operation temperature. If the engine is running cold you will have more condensation in the crankcase that does not burn of and will condense in the oil fill cap area.

Forget about the dash gauge, you need to bring up the Hidden OBC Menu and check the coolant temp. It should be consistently running between 88-95C.

See 3rd link below in my signature.

These stats soft fail and open too early and run cold when they go bad. This is a common problem.
 
#11 ·
yes i am going to replace them , and yes i live in Arkansas and usually it doesnt get too awfully cold...but on Christmas it snowed alot and has been around 19 degrees almost every morning. What temp is that in Fahrenheit ?
 
#14 ·
Do me a favor and report back what the engine temp is running, this would be helpful for many to understand more about this issue.

Since you live in the South, you may never realize your thermostat is weak/soft until you really pay attention to it.

Remember that the coolant gauge is buffered and will stay at the 12'oclock position over a 50F range so you cannot really rely on the gauge to keep you properly informed of the thermostat condition.
 
#15 ·
Talking about the 88-95c, and to my surprise i had zero when i replaced the "separator to valve cover" hose 3 weeks ago.
I broke it when i replaced the valve cover gasket. But all my troubles began on the morning after it snowed...battery even started funny
 
#16 ·
jesus, how the heck you could replace just a part of the CCV system without tearing the rest of it to shreds since it's all bacon by this point anyway in your 1999 is beyond me.

I had the yellow "goo" appear a few times in my car under the oil cap. It comes from running the car around town and not really letting her warm up fully. If you do a lot of around town driving, then get her out on the highway and run her for a good long time. Hour or more, or a road trip even better! You should notice the yellow goo going away under the oil cap. But please don't ignore the rest of the ccv system, you should really replace it all as soon as you can, you may have cracked another hose replacing that one you already did or the separator, they are so so so so brittle, which is why most DIY's tell you to just break it apart in your hands when removing it rather than try to remove it the way it was connected.
 
#18 ·
So what temp is the engine actually running at?

Again, would be interested to see if many of these problems are due to cold running engines.

Kind of like dealing with my teens, how many times do I have to ask!
 
#19 ·
Example of carnage that occurred when I removed my wife's:

Image
 
#20 ·
@Trizzuth: I removed the power steering reservoir , from there you just remove the oil filter sensor (or whatever that is exactly) and you got a straight shot to where it meets the separator. You can't see it but there is just enough room to squeeze you hand in there and get it done. @jfoj: do I go into the secret on board computer to the temp and just take off?
 
#21 ·
Yeah, I did this too, unfortunately for me in this case, I have giant paws and it's a challenge to shove my hands anywhere in the engine normally.. I did most of this job blind using only feel to verify things were connected. Honestly, worst part is getting the effing dipstick tube back in with that O-ring, what a **** ty design that is. jesus.
 
#22 ·
@trizzuth: is the dip stick tube plastic or metal? Cause I read that you can take it out and blow it clean with compressed air and reuse it. Also I believe it is actin up because of my car not reaching operating temp. I drive 35 miles a day to work and it barely moves above the blue marks.
 
#24 ·
Metal, if you're gonna do the ccv, blow into it when you've got the separator to dipstick hose off.

I didn't have to do it, but i've heard getting the dipstick tube "O" ring seated is a PITA. I'd avoid removing the dipstick tube.
 
#25 · (Edited)
75-80C is too low if you had been on the road for more than 10 mins. If the temps do not get to 90C in fairly short order, you likely need a thermostat.

An engine running too cold will not cook off the water vapor, moisture and fuel in the crankcase.
 
#26 ·
I was afraid of that, so i had one ordered as well...So will i need to change my oil after the hoses and thermostat are installed?
And how long will this probably take me to replace the CCV hoses?

E46 EXPERIENCE INCLUDES:
*Oil change
*all intake boots
*removed and cleaned DISA and ICV
*transmission and diff fluid change
*Radiator and complete hose replacement
*Complete power steering over haul(minus Rack and pinion) and the pump twice
* replaced Valve Cover Gasket
* Replaced oil housing filter gasket
 
#27 ·
If you're gonna blast the dipstick tube and there is gunk in there then ya change your oil.

It took me about 6 hours going nice and slow. The hardest part about it is your working by braille for a lot of it.
From what you've described above, it's well within your abilities.
 
#28 ·
Pull your dipstick tube and clean it out as well. There is also an O-ring on the dipstick tube that should be replaced as well.

The trick to really cleaning the double wall dipstick tube is to find an old windshield wipers and use one of the metal rear supports to break all the crap loose. You could also use some stiff wire as well.

Lots of carb or break cleaner and compressed air does not hurt either.
 
#32 ·
Remember that the coolant gauge is buffered and will stay at the 12'oclock position over a 50F range




So it is"buffered," as you say. I always figured it was little more than an idiot light in disguise. Riding a Honda VFR with a real gauge, it's amazing how fast and far the coolant temperature will rise when the throttle is twisted
 
#33 ·
It is kind of an idiot gauge. The reason the gauge is buffered is because the thermostat has an electrical heating element that will actually reduce the coolant temp under hard driving conditions as well as a few other conditions. This way the behavior is isolated from the driver so they do not complain about a possible problem if the temps vary a great deal.

I do not recall the exact figures and behavior, however, the gauge may stay at 12'oclock even down to as low as 170F or 77C when the engine should run around 88-95C or 190-203F. These stats and many others typically fail and open too early and run too cold due to weak springs. This is not uncommon to find very often.
 
#36 · (Edited)
Not exactly as you think the thermostat behaves.

There is actually an electrical heating element in the thermostat that allows the DME to heat the thermostat up and force it to open prematurely to lower the engine cooling temp.

Example when under heavy throttle, the thermostat heater opens the thermostat to make it behave like a lower temperature thermostat, allowing water to move in greater volume through the engine and force the engine temperature down.

The DME actually predicts and pre-emtively counters the additional heat load, counter acts and actually can swing to the cooler side for better performance and reduced chances of engine knock. If you end up with engine knock the sensors detect this, retard the timing and in turn this reduces the engine power and performance.

Kind of helps balance fuel economy, emissions, engine wear and performance.