[QUOTE=donkeyballs;5302255]Dude I get the same high pitch noise at WOT towards the upper end of the RPM. I think it sounds more like a whine. Its like secondary audible noise over the turbo spool noise.

It does it on the stock tune, and it REALLY does it well on the BYT tune. I thought it was normal since it seemed to be related to how much boost im pushing. About 16 psi and above 5500rpms I can hear it.

 

Ive actually been having this problem the last week and a half.. Its a loud squeak and sounds almost like a loose belt or somethin, but nuthin seems to be loose.. I have an injen CAI btw.. Ima check today of the oil filler cap trips on me lol
Only thing I've noticed about the 'sound' is, it comes at LOW rpms.. Like when taking off.. Barely ever in first.. Only in 2nd actually, when goin from a Rollin start..(light a light that turns green as you come to it)
I don't know if this is the same problem, but it sounds oh so familiar..

 

I also have a vacuum in the crank case. when removing the oil fill cap you can feel it sucking the cap some. I don't have the high pitch noise but i did notice today after revving the engine a couple of times about half throttle, after letting off the throttle white/grey smoke will come out of exhaust for a few seconds then stop. under normal driving conditions theres no smoke. I checked all fluids, coolant level is fine, oil level is fine and oil is not creamy/white its normal. I don't recall the pressure on the oil cap being has much as it is now. Also get a quite fart like sound from exhaust every 10 seconds or so and a rattle from exhaust. Car is stock except for injen CAI. Only CEL is the common lean bank one that will come on a couple months and clear itself.... any ideas?

 

Maybe I don't know enough about this stuff to be talking. I'm certainly no expert but it seems to me that the intake REALLY didn't have anything to do with it. It would have done it from day one in that case, am I right?
There must be a blockage or some problem in the crankcase ventilation. Oil sludge perhaps is restricting flow after building up over time.

 

Suggestions on fix for said blockage?

 

Well I'm just taking completely inexperienced guesses here.

But I would guess the metal braided line from the turbo to the valve cover where the oil catch cans get hooked up.
Which would be a PIA. But something has to be messed up in the vent system. Maybe I'll look at it in more detail. If a person knew more about how exactly it works, the fact that it's drawing a strong vacuum could point to the line(s) that are the culprit.


EDIT: Doing research right now. I found one confirmed case where someone bought a PCV Kit (different car and different vent system of course). They replaced the parts with the kit and the problem went away. I'll keep searching though.

EDIT #2: Okay I did some searching. I found 2 confirmed cases of the PCV system being at fault. One case of leaking intake manifold (on a V6), and one case of intake valve not opening like it should on an LS1. Those are confirmed fixes that others posted for this issue on other engines.

 

alright been searching the forum for hours, where is the PCV valve located and does anyone know the part #. I found one for LNF are they the same? AC Delco # 12589440

 

IIRC the LNF doesn't actually have a valve. It's just a ventilation system but oil vapors circulate and I don't see why they couldn't accumulate and restrict flow. There's baffling in the valve cover to catch the oil vapors. Just a thought though.

EDIT: I just did a little more research. I found an interesting article that was actually talking about carbon buildup on valves but the blame was put on the crankcase ventilation

Just from a Google search of "LNF Crankcase Ventilation" I also found a few sites selling the vent tubes (turbo to valve cover tube - same one that oil catch cans use) for sale. Which just kind of clues me in to maybe it's a little bit of a known issue..?

Here's a tidbit taken from that article.
"Tony Chick, principal engineer at European Performance Labs in Stratford, Connecticut, has made a career of repairing and rebuilding high-performance engines from Audi, Porsche AG and BMW, among others and his operation has garnered a reputation among car enthusiasts as a go-to place for cleaning DI engines that have become choked with carbon. Chick thinks the problem for most affected engines can be traced to the breathing system – specifically, the design of its crankcase ventilation and exhaust-gas recirculation components.

All modern gasoline engines return some crankcase and exhaust gases back through the intake manifold in order to help control emissions, but, according to Chick, some exhaust-gas recirculation designs are “dirtier" than others. Some, he said, are less-effective at preventing the passage of tiny bits of oil, carbon and other particulates that eventually get baked onto the intake ports and valves.

There is no simple fix for engines that are prone to carbon build-up, Chick says. What’s needed is a complete redesign of the crankcase ventilation and exhaust-gas recirculation systems to prevent particulates from getting through."

 

Powell is working on something related to this.

 

I believe it's the one that attaches to the intake from the breather line that comes from the valve cover. It's got a check valve incorporated in it.

LNF PCV Valve 12589440




Like this, but in our case, it's between the MAF and valve cover.

 

Mine made this sound when I installed a Forge by-pass valve with the yellow spring. It went away when I installed the green spring.