Noise a search can't diagnose

[Nitrew]

This is not the way I wanted to intro myself. I especially did not want my first post be a long BS cry for help like this... but oh well. I have been a member for 8 mos, a lurker for about 2 years and have all but worn out the search function (as well as on AW and AF) since that time. I am new here but not to forums (I am a mod on an Acura forum) and have finally gotten to the point where a search cannot answer my question, or at least give me an answer different than the one I don't want to hear. I chose to pose my question here as (being a mod on another site for 5 years) the most quality, hands-on, to-the-point information seems to be on this site. Anyway...

As my profile says I have a 1999 A4 1.8TQT (AEB). I will list only my engine mods, for reference (although I don't see how any would be relevant to my problem).

Under the hood:
->GIAC pc-16 K04 file (ecu sitting in the garage, not installed, running stock right now)
->K04
->eBay FMIC
->2.5” hard IC piping (DIY)
->ECS manual fuel pressure regulator
->TT (225hp) DV
->NGK BKR6E @ ~.030
->Eurocode 2.5” test pipe (EGT bung / heat wrapped / nonfoulers)
->Heat-wrapped downpipe
->ECS lightweight pulley
->Dual efk (DIY, 14”/2500 CFM, 10”/1250 CFM, pulley/clutch delete)

Other crap:
->GReddy FA Turbo Timer (DIY mount)
->GReddy Profec B-Spec II boost controller (DIY mount)
->GReddy boost meter (DIY mount)
->GReddy EGT meter (DIY mount)
->Turbo Timer Companion Lite (DIY on/off)
->Power steering cooler (DIY)
->Low temp fan switch
->Low temp thermostat

So one month ago I replaced the timing belt, all accessory belts, head gasket, crank pulley, oil (added Lucas oil stabilizer), deleted the pulley driven fan (as well as the clutch and rotating assembly), VC gasket set, head bolts, oil return line, thermostat, fan switch, coolant resivoir tank, added the EBC, new coolant, turbo (up'd to K04) and gaskets, EM gasket, IM gasket, installed TP with relevant new gaskets, spark plugs, new ATF fluid and filter, and most all of my vac lines. All this in preperation for the new GIAC pc-16 ecu.

The car ran great for a while (about 1 month). I could hold a steady 12psi (actually higher, but I held back on purpose), engine ran whisper quiet, and pulled like a bitch. The exhaust leak caused me to turn off the ebc and run @4psi til I got time to address it.

Now on to the problem. A very weird intermitent grinding noise. It sounded like it was comming from the turbo (installed 1 month ago, >1k miles) since I had an exhaust leak at the EM/turbo gasket. I have since fixed this, and the problem persists. I pulled the front end and the turbo fins do not show signs of housing contact nor is there any shaft play. With the front end off I checked the timing... spot on. Oil is clean and level is good. No CEL, no oil level light. WTF?

I have come to the conclusion that over the course of the last month the stabilizer additive has loosened up some sludge and consequently that is clogging the heads oil ports (even though I have used Prolong in the past without issue), for some unknown reason not tripping the idiot light. It came on so sudden though, no build up or warning. "Running ok at 4psi" straight to "I am scared to start and idle the thing", over the course of one test drive. I VAG-COM checked the car and got a bad ecu code. Cleared it, replaced the ecu -> no CEL, but still this godawful noise. I am trying to avoid filling the crankcase with 5 gallons of deisel fuel, being a car guy who has not had to pay a mechanic for over 11 years, there is just something fundamentally fucked up about that.

Here are two videos trying to capture the noise. I know one of the EM turbo mount bolts moves, like I said the EM exhaust leak has been fixed, the sound is just easier to hear with an exhaust gas vent to the atomsphere:

Vid 1
Vid 2

This damn novel I wrote should cover all the pertinent bases for some diagnostic help. Any advice is much appreciated.

[zrowcool]

i really would have to say the turbo... that grinding sounds horrible. i know you said it was new but it sounds like the bearing to me. maybe a clogged feed line? if it was me i would change the oil asap and try some kind of flush. i know the diesel kerosene sounds harsh but even something like seafoam. then put some synthetic without the additive. hopefully it will get better and not cost you a new turbo

[Nitrew]

I have seafoamed the car twice in the past and when I swapped in the new trubo I checked for a clogged return and feed. I also had a long phone call with the shop where I bought the turbo and according to them "turbo problems aren't intermitent, they go out or they don't". It kind of made sense, especially since the car was still able to boost, and the noise only happened recently. Why would the turbo bearing all the sudden go out after ~1000 miles?

Honestly I hope it is the turbo, it has a warranty.

[aaronz]

I would see if you can get Old guy in on this one.

[Nitrew]

Old guy

who?

[djwimbo]

Dude, the rear bolt holding the turbo to the manifold is either A loose or B too long. Look at the second video, when the RPM's come up you can see the washer/bolt rattle.

Get that tight, or the correct length then re-diag.

[Nitrew]

Dude, the rear bolt holding the turbo to the manifold is either A loose or B too long. Look at the second video, when the RPM's come up you can see the washer/bolt rattle.

Get that tight, or the correct length then re-diag.

Ummm....

...The exhaust leak caused me to turn off the ebc and run @4psi til I got time to address it....

...It sounded like it was comming from the turbo (installed 1 month ago, >1k miles) since I had an exhaust leak at the EM/turbo gasket. I have since fixed this, and the problem persists....

...I know one of the EM turbo mount bolts moves, like I said the EM exhaust leak has been fixed, the sound is just easier to hear with an exhaust gas vent to the atomsphere...

It has been fixed, and re-diag'd... no change.

[Nitrew]

Really? No ideas on this?

I really don't want to rebuild the head and soak the crankcase in deisel.