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nextNME nextNME is offline
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Car: 2008 535xi
Default Understanding the Valve Cover PCV system - 04-28-2019, 07:08 PM

What symptoms would occur with a faulty internal valve cover PCV system?

What part, if any, would the valve cover internal PCV system have with turbos blowing oil?

Background: my 2008 535xi (98k mi. stock turbo) is leaking oil, sometimes. More like a gelatinous discharge. Passenger side, rear turbo area. Spotted oil dripped down the frame, onto the control arm bushings where it meets the frame, on the axle boot above that, and frame above that axle boot.
I have yet to recreate this leak, doesn't happen under light driving?
The spot on the ground was a jelly like consistency... but was oil.
Does not appear to be the oil pan. New valve cover gasket replaced. No other oil leaks that I can spot.
No burning oil smell.
No low oil indicator.
Pressure test - no leaks on valve cover or other.
- - but pressurized air coming out the oil fill cap?
Oil catch can has little to no oil accumulated (+500mi).
New PCV flapper valve and FTP N54 PCV Valve Upgraded Replacement
No codes. Engine runs good. Medium waste gate rattle (hidden by JB4).
Boost is -1.5psi from target.
Turbo drain line clogged?
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Vorsprung_CJB Vorsprung_CJB is offline
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Car: 135i N54
Default 04-29-2019, 08:45 AM

Sure it wasn't CV grease? Seems more like the consistency you describe. Or it was something you picked up off the road (like grease/lube from big rigs)? Seems like the area is far enough from the turbos I wouldn't expect it to accumulate there.
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iminhell1 iminhell1 is offline
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Car: 2010 135i
Default 04-29-2019, 10:36 AM

I'll take blown motor mount for $200 Alex.

2010 135i auto,
2020 mods: Speedtech S366, VTT DBBL, PR Coils, dual 450's, etc
Best stock turbo 1/8 mile: 7.469 @ 98.56, 1.769 60'
Best stock turbo 1/4 mile: 11.480 @ 121.79 1.802 60'
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nextNME nextNME is offline
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Car: 2008 535xi
Default 04-29-2019, 06:28 PM

CV grease I'd say maybe. But the boot looks okay, no obvious cracks... a bit oily tho. The location and amount make me think it's leaking oil somewhere. The underbody panels are in place year round... took them off when I saw seepage near the control arm.

The spray pattern up on the frame was interesting. Either a squirt out the side of the turbo dripping down the heat shield, and slung up off the axle... I don't know. There's no burning oil smell at all. But there's a significant amount of dirty oil and jelly stuff up there. On the steering rack even, I thought it was the oil pan at first. I have never gotten a low oil indicator. Trusted shop did all the fluids 2 months ago and said how good the car was running. Which it is...

So I hosed it off good without the panels. and that's as far as I've got.

It's hard to see where the oil starts. I highlighted red where the oil was collecting. Stock photos from Pelican Parts. I claim no rights to the image

What is the concern with the motor mount?
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arkie6 arkie6 is offline
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Car: 2008 335i
Default 05-16-2019, 11:26 AM

Originally Posted by nextNME
...What is the concern with the motor mount?
Well, the right side motor mount is in that area and it is oil filled (hydraulic design). Failed hydraulic motor mounts can allow the engine to drop down ~10mm or 3/8" and allow the power steering pump pulley to hit the cross member which can in turn crack the pulley which can then result in a shredded serpentine belt which can get sucked into the front crankshaft seal behind the harmonic balancer. These pieces of shredded belt can then clog your oil pump pickup screen which can starve the engine of oil and result in wiped bearings / seized engine. All that from a failed motor mount.
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nextNME nextNME is offline
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Car: 2008 535xi
Default 05-16-2019, 12:32 PM

Thank you arkie6, I'll have to take a look there also.

I brought it back to the shop, just for them to take a look, and a cleaning, and they said that it was oil from the intercooler, or doing the boost leak test. I realized that I did NOT cap the PCV return tube at the heater element...
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