05 STI Oil from around turbo.

[SiriusBlack]

Hey all, got a bit of a problem. I have an 05 WRX STI that I got used with 70,000 miles on it. Owner said the engine had been swapped with a 20,000 mile unit. I have owned the car almost a year now.

Mods it came with:

Invidia cat back exhaust.

Cobb intake

Grimspeed turbo solenoid

AOS of unknown brand

Aluminum mishimoto radiator

Cobb accessport running stage 1 tune of unknown origin.

Mods I installed:

Killerbee oil pickup 

Prosport oil pressure and voltage gauges.

I run Castrol 5W30 premium full synthetic.

Now on to the problem. I was driving home one night, about 12 miles. I was driving spiritedly, but definitely not thrashing it. I pull into a gas station at the edge of the town I live in and notice smoke from under the hood. There is oil all over the passenger side strut tower and on the turbo and down pipe. I check the oil level, and it's right on the money. I decide to drive it the 8 blocks home and keep a close eye on the oil pressure. Oil pressure is fine all the way home, I open the hood and check again. There doesn't appear to be any additional oil on the strut tower or surrounding area.

I have thought for awhile that it gets hotter under the hood than it ought to, but my temp gauge never climbs past the third mark up that's before the red zone.

I have yet to pull it apart and look in depth, in the meantime anyone have any ideas as to what may have happened? My current theory is that the banjo bolt for the oil line on top of the turbo went bad.

As always, thanks in advance.

 

 

 

[1 Lucky Texan]

sure it's oil and not CV grease from a split boot? could it be power steering fluid?

maybe there's a way to pressurize the oil system manually to look for leaks....

 

 

[SiriusBlack]

1 hour ago, 1 Lucky Texan said:

sure it's oil and not CV grease from a split boot? could it be power steering fluid?

maybe there's a way to pressurize the oil system manually to look for leaks....

 

 

Reasonably sure. It sure as hell looked like engine oil, but by that same token it was dark out. So I'm not 100% sure.

[GeneralDisorder]

Throw away the AOS. Those are for idiots and people with blown engines. Buy all the factory PCV and breather hoses and put it back to stock. 

Make sure the turbo stay brackets are in place. If those are loose or missing it can lead to flexing of the oil supply line to the turbo and they can crack. 

Also if you don't know the origin of the tune - get it properly pro-tuned on a dyno before a previous owners bad decision claims your rod bearings. 

GD

Edited September 22, 2022 by GeneralDisorder

[GeneralDisorder]

2 minutes ago, GeneralDisorder said:

Fail. 

 

Edited September 22, 2022 by GeneralDisorder

[jonathan909]

17 hours ago, GeneralDisorder said:

Throw away the AOS. Those are for idiots and people with blown engines. Buy all the factory PCV and breather hoses and put it back to stock.

Living out in the woods, I've never run across one of these things in the wild.  Seems like a solution in search of a problem.  I mean, how much oil will it actually recover in an engine that still has half-decent compression?

[GeneralDisorder]

6 hours ago, jonathan909 said:

Living out in the woods, I've never run across one of these things in the wild.  Seems like a solution in search of a problem.  I mean, how much oil will it actually recover in an engine that still has half-decent compression?

Usually almost nothing on a good engine. And the name is HIGHLY misleading. They are ABSOLUTELY NOT "Air/Oil Separators" - they are "Air/Liquid Separators" and the distinction is very relevant since engines produce large amounts of condensation during warm up. This is generally directed into the cylinders and burnt by the stock breather system. In an AOS it is saved and mixed with the normal small amount of oil vapor to produce a nasty concoction of milkshake-esque sludge that coats and restricts the normal operation of the PCV and breather system. 

It is honestly a horrible idea for a street vehicle. Catch cans and AOSs are RACE CAR parts. They can serve a function in a racing environment to solve specific problems related to ulta-high performance engines. These are engines that see intermittent use and have highly accelerated maintenance requirements - part of which is to clean and service these accessory systems to prevent clogging and empty collection vessels, etc. These are NOT appropriate for street use. 

GD

[SiriusBlack]

Alright, I just finished pulling the car apart. The turbo is PRISTINE. No residue, no shaft slop, nothing. There is oil all over the turbo oil drain hose and the gasket for the metal hose barb, where it bolts to the bottom of the turbo doesn't look very good. So I'm going to replace that gasket and others while I have it out. I will also replace the small rubber oil drain hose, and look into deleting the AOS the previous owner installed.

Currently we're working under the hypothesis that the PCV system over pressurized and blew the excess pressure out that drain line, since it's the path of least resistance.

[nvu]

While you're there, swap out the metal oil inlet pipe for a braided steel one.  Those lines eventually crack near the joints if you fiddle with them to swap turbos.

[SiriusBlack]

On 9/24/2022 at 6:51 PM, nvu said:

While you're there, swap out the metal oil inlet pipe for a braided steel one.  Those lines eventually crack near the joints if you fiddle with them to swap turbos.

Done. I got stainless steel braided oil lines installed. Now I'm in the process of putting the PCV system back to stock. Looks like they deleted my PCV valve when they installed the AOS.

[nvu]

If you've gotten most of the upper engine apart, might as well do a compression test.  Not having blowby and suddenly having a lot of blowby might point to cracked piston ringlands.  It's peace of mind to have it done anyways.

[1 Lucky Texan]

@GeneralDisorder would his engine be a candidate for a Killer B oil pickup?

[SiriusBlack]

On 10/3/2022 at 4:07 PM, nvu said:

If you've gotten most of the upper engine apart, might as well do a compression test.  Not having blowby and suddenly having a lot of blowby might point to cracked piston ringlands.  It's peace of mind to have it done anyways.

I was thinking about that. I don't think they are, as it ran completely fine besides the oil leak. I just pray they haven't cracked. My shop setup is non-existent, I've been doing repairs in my driveway all these years.

[GeneralDisorder]

On 10/4/2022 at 11:20 AM, 1 Lucky Texan said:

@GeneralDisorder would his engine be a candidate for a Killer B oil pickup?

  Absolutely. '04 to '06 are the most common years for pickup tube failures. 

GD

[nvu]

14 hours ago, SiriusBlack said:

I was thinking about that. I don't think they are, as it ran completely fine besides the oil leak. I just pray they haven't cracked. My shop setup is non-existent, I've been doing repairs in my driveway all these years.

You can do it in the driveway next spark plug change, a compression tester and a remote starter switch is all you need.  Clamp the switch on the starter and press to spin it.  The key doesn't even need to be in ignition and you don't have to deal with hassle of removing fuel pump relays.  Do the clamping with the battery unplugged, you don't want the starter kicking in while you're reaching behind trying to clamp things.

[SiriusBlack]

On 10/6/2022 at 12:42 AM, nvu said:

You can do it in the driveway next spark plug change, a compression tester and a remote starter switch is all you need.  Clamp the switch on the starter and press to spin it.  The key doesn't even need to be in ignition and you don't have to deal with hassle of removing fuel pump relays.  Do the clamping with the battery unplugged, you don't want the starter kicking in while you're reaching behind trying to clamp things.

I wasn't worried about doing the test in my driveway, I was worried about replacing the pistons in my driveway should the ringlands be cracked. I'll be doing the compression test soon. 

@1 Lucky Texan I already installed a killer bee pickup in it awhile back.

[GeneralDisorder]

Compression test really won't show an early stage ringland issue. 

Oil consumption is typically higher in that cylinder. 

You can just do a cranking cadence test. Push in the clutch and hold the gas pedal all the way down. This will shut off the injectors and put the computer into "flood clear" mode. When you crank it you can then listen to the engine. If it sounds like every cylinder is even then it's likely fine. If it sounds like you would imagine the theme song to a three-legged dog would sound then you have an issue. We do this as a first step on cars with consistent idle misfires, etc. \

The best insurance against ringland failures is a good tuner that knows how to keep them from breaking. Detonation is what does it, and the factory Subaru maps as well as some of the COBB maps have as much as 8 degrees too much timing in them. We have pulled 8-9 degrees out of some of the cars and only lost about 2 HP. That's a massive safety factor gain. 

GD

[el_freddo]

46 minutes ago, GeneralDisorder said:

We have pulled 8-9 degrees out of some of the cars and only lost about 2 HP. That's a massive safety factor gain. 

That’s a huge amount of timing for very little performance loss! Quite impressive when you think about it and a no brainer too.

Cheers 

Bennie

[SiriusBlack]

@GeneralDisorder I have my engine mostly back together. However I have found a hose barb that appears to have been welded or brazed to the back of the drivers side valve cover. It had a hose from the bottom of the AOS I removed, going to it. From all the pictures I've seen of this engine, I assume that barb is not factory?

Thanks in advance.

[GeneralDisorder]

1 hour ago, SiriusBlack said:

@GeneralDisorder I have my engine mostly back together. However I have found a hose barb that appears to have been welded or brazed to the back of the drivers side valve cover. It had a hose from the bottom of the AOS I removed, going to it. From all the pictures I've seen of this engine, I assume that barb is not factory?

Thanks in advance.

Never seen such a modification. I would plug it if you are removing the AOS. If you can I would suggest removing the valve cover, and tapping the hole used by the barb fitting for an NPT brass Allen plug. 

GD