Subaru Enthusiasts Car Club of the Sierras

Subaru Enthusiasts Car Club of the Sierras (https://www.seccs.org/forums/index.php)

- Technical Chat (https://www.seccs.org/forums/forumdisplay.php?f=11)

- - Turbo Issue (https://www.seccs.org/forums/showthread.php?t=8946)

Quitting smoking is good for the candy habit.

btw Nick just had your same issue, lots of oil out of the exhaust, and then it 'went away" the next day.. maybe it is a cold and its going around.... ?

Subaru Syphilis

Don't park next to me

Quote:

Originally Posted by cody (Post 151203)

So after I took my 6 runs in the morning, yesterday, I left my car idling, accidentally. I went to shag cones and Amanda stayed on grid. She didn't notice that I had left the car running until, a couple hours later when she saw "a bunch of smoke coming out of the exhaust" and shut it down.

When I started it up and checked I did see a bit of whitish smoke coming out of the exhaust but no hint of sweet coolant smell. It just smelled like fuel...and not even all that much. BTW, don't huff exhaust at home, kids. :alien:

So I think everything's probably fine until I come off my first RNP run in the afternoon and when I park it, it's the return of the lovely reoccurring oil smoke-out-the-hood-scoop trick, although I doubt it's related to the old issue, a leaking inlet pipe (now replaced with a Perrin). When I take a look, I see hot smoke coming off the bottom of the turbo. After a couple minutes the smoke subsided and I could see fresh oil on the CV boot below the turbo, but I don't think I lost enough to make a pool on the ground or anything. Later I smelled the oil from the CV boot and it didn't smell strongly so I doubt it's oil from the gearbox filltube, but the gearbox dipstick wasn't pushed all the way in so who knows.

People commented that during my afternoon run, my car was blowing smoke out the exhaust, but I neglected to ask what color, unfortunately. :mad: Anybody remember?

So thanks to Kevin and Nina for following me back to Reno from RFR. When I got home, there was no oil smoke. It doesn't seem like I lost very much oil yesterday, maybe third of a quart? From under the car there was a little evidence of oil leaking, but not a lot. The oil on the CV boot had lessened and was no longer wet and shiny. I checked the oil line fitting (banjo bolt?) on the top of the turbo and it was tight. I was looking at my spare stock turbo and there is a two bolt flange fitting on the bottom for oil return (I'm assuming) that could be the culprit. Maybe idling so long vibrated the bolts loose or something. But I can't get to those bolts without removing the turbo, or so it seems.

But what would cause both white exhaust and an oil leak from the turbo or are they unrelated issues or perhaps loosely connected...like oil leaking internally and externally from the turbo and when the internal oil gets burned, it causes knock, causing the white smoke somehow? I don't know.

This issue returned at the autocross today. After my first run, there was smoke coming out of the hood scoop. I popped the hood and it was coming from underneath the turbo heat shield, presumably from the turbo itself. I assumed it was simply oil burning off the turbo. I did just change my gear oil, after all. And it slowly subsided as I took more runs. It seemed to completely disappear by my 3rd or 4th run. Unfortunately, after my first RNP run in the afternoon, several people commented that my car was blowing tons of smoke out of the exhaust. And the smoke from under the turbo heat shield returned. I said Fuck it and just kept driving through all 5 RNP runs and it seemed to subside again.

I just checked both my gear and motor oil levels and they're both perfect. As far as I can tell, I haven't lost any of either since I checked them yesterday. What could cause both smoke out the tailpipe and smoke from the turbo at the same time? Turbo oil seal leak getting into the DP and leaking out through the DP/Turbo gasket? I have a very low mileage stock turbo in my garage, but when Cory checked this out for me last year, he couldn't recreate the issue so he couldn't recommend swapping out the turbo...

Pull your heat shield and see if you can see evidence of a leak. The way this is smoking both from the tailpipe and from under the hood makes me suspect a turbo oil seal. If you can see evidence of oil anywhere on your turbo or exhaust, go ahead and swap the other turbo on when you get a chance. If that doesn't fix it, you've either got an internal issue, a breather/PCV issue, or another bad turbo. :p

No evidence of oil when I pulled the heatshield this morning. The car ran great and didn't smoke out the hood or tailpipe at autocross all day. It even got faster in the afternoon. :)

I'm going to pull the IC and Y-pipe. If there is significant oil in there, I'll take it to Kspeed to have them swap the turbo. If not, I might just wait for it to get worse. Thoughts? I'd rather error on the side of safety if anyone thinks I should just swap the turbo to be safe.

Doing a turbo swap isn't to bad Cody, I'm sure you could do it yourself. Its just a little messy and a little time consuming. Plus, with that Perrin inlet you won't have to worry about tearing the hell out of the stock inlet pipe.

Yeah, I'd rather just have a professional handle it for peace of mind, plus I'm just not as motivated to do mods myself any more. I'm cool with just handling maintenance on my own. :)

I took some pics. I'll add some notes in the next post.

After removing the IC and looking under it and the turbo, I did find some oil but I'm not sure where it's coming from. Just like when I had this issue last year, I see evidence of oil on the CV boot below the turbo. That's what you see in the third pic.

Additionally the first two pics show some oil seeping out of or onto hoses below where the turbo hits the Y-Pipe. However the inside of the Y pipe, IC and turbo appear to be pretty darn clean. Same with the throttle body. I guess it seems like oil is coming out of the bottom/side of the turbo closest to the motor and getting on those hoses (first two pics) or coming from them? I don't know but it doesn't seem like a big deal...I hope.

Different sources. oil in the intake is likely vapor from the breathers that slows down in the volume of the intercooler/condenses and falls out of the air stream.

That is standard without an AOS.

The stuff under the turbo is likely a loose banjo, missing copper washer or leaking rubber hose.

Quote:

Originally Posted by Dean (Post 156259)

Okay, but the issue is very intermittent and oil smoke appears from both sources simultaneously (I'm not seeing one issue without the other), so I can't imagine there's more than one issue here. How would a leaking banjo fitting or hose cause the tailpipe smoke?

Edit: and I don't know what you mean by oil in the intake. I probably could have been more clear, but the intake tract has no significant oil residue.

I meant intercooler, throttle body and beyond. Some might be in the turbo inlet hose after the beather fittings but more likely in/past IC.

Blow by causes the oil in the breathers and thus out the exhaust. Those likely have nothing to do with an external leak.

How do you see the drip when driving to see the smoke? Other than the oil system being at higher pressure at higher RPM, there really is little link between internal and external oil. Even oil leaking past the bushing in the turbo and into the IC inlet is not going to leak outside the turbo. Thus, two sources.

I really don't think there's excess oil in the TB, IC or inlet hose. I didn't actually look inside the inlet hose, but it's upstream from the rest so I think I'd see it if it existed.

My theory is that oil is leaking internally in the turbo where the turbo hits the DP and while some stays inside the exhaust tract, some is leaking out the Turbo/DP gasket. When the turbo gets red hot, it burns both internal and external oil. Thing is if oil can leak out that gasket, so would sound. Would I hear an exhaust leak if I had one there?

Your picture of the TB shows a typical bit. Thought you said IC had a bit too.

A hose that holds 15-20PSI does not drip oil typically without causing much worse problems since they would represent a post MAF air leak. Any oil leak inside the turbo would be immediately atomized on the compressor side and again some would fall out of suspension in the IC, more would burn and come out the exhaust. Anything on the turbine side would be vaporize and burned in the turbo/DP/cat or thrown out the tail pipe in a catless environment.

The only easy way for oil to come out of the turbo is a oil line. Until you eliminate that, looking for more obscure ones are a stretch IMHO.

I may be dead wrong, but just trying to give you likely scenarios.

So, pull the IC and turbo heat shield to get to the oil feed lines and check that they're tight/not leaking?

This is the way I see it. The seal on your turbo is probably bad. I am on my second TD04 and the seal is going on this one just like it went on the first. I never see any smoke out of the exhaust until I hit full boost pressure. Then I can look in the mirror and see a little smoke behind me. I would suggest that you make a weekend available to swap this turbo with the one in your garage and see if that fixes the problem. At the least you will get a good look at everything once the turbo is out and out of the way.

^Thanks, Joel. I'm sure you're probably right.

Quote:

Originally Posted by 100_Percent_Juice (Post 156271)

This is the way I see it. The seal on your turbo is probably bad...

Not disagreeing, but again a seal is not going to create any external leakage as he is describing and the symptoms are very similar to blow by and/or breather issues. Unless you have a catch can or an AOS, it is really hard to find out which it is.

I have a catch can but never had the balls to install it.

So, pull the IC and turbo heat shield to get to the oil feed lines and check that they're tight/not leaking?

Quote:

Originally Posted by cody (Post 156274)

I have a catch can but never had the balls to install it.

So, pull the IC and turbo heat shield to get to the oil feed lines and check that they're tight/not leaking?

Chances are the leak is a cracked or loose low pressure return hose on te bottom of the turbo. If the high pressure fitting is leaking, it'd be spraying oil all over the place. Plus, it's much less likely to leak since it's a nice braided/fitted line, while the other is a plain old rubber hose with clamps on it.

I'd do like juice said: swap the turbo this weekend. Make sure you replace the low pressure oil return line with a new piece of hose. If that doesn't fix it, the worst case is you wasted a couple of hours of time and got a fresh turbo on the car. Plus, you'll be able to check out everything closely while the turbo is off the car.

Keep in mind, you're eventually going to lose a turbo, it's just a matter of time. Might as well swap it preemptively, and keep the high mileage turbo as a backup in case the lower one blows up without warning.

I did check the return hose (as well as I could) when I had this same issue last year and it showed zero evidence of oil leaking, but it could be that the oil just burns off of it I guess. Thanks for the input guys. I have plans to drive to Sonoma County this weekend so I might just try to get Cory to do the swap before then if he has time.