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Discussion Starter #1
Posted in a couple other places, looking for some more input.

08 LNF SS

My old stock turbo blew, I replaced it with a seemingly perfect stocker with absolutely no shaft play.
I cleaned all the piping, intercooler, & everything getting old residue out. So the smoke isn't old stuff.
The car only smokes at idle or if you throw it in neutral after driving on reacceleration it will start smoking. The car doesn't smoke under boost, or normal driving conditions at all.

Myself & a very skilled mechanic looked at the car last night trying to figure out the issue. We were fairly crunched on time but ruled it down to 2 things it would have to be.

1. The exhaust side of the turbo seal is blown.
or 2. The breather line from the valve cover to the turbo isn't functioning correctly.

Any input is greatly appreciated!
 

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Levee
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I need more information regarding the last turbo blowing. Was it just the seals or was there more than just that?

Also are you tuned to run more boost than 20psi?

Do you have any oil residue on the compressor side of the turbo or is that clean?

1. The exhaust side of the turbo seal being blown would cause smoking under boost as when you're boosting you're getting more oil pressure.

2. The breather line from the Valve cover to turbo can actually draw oil in from the valve cover/head to the turbo, this is why i said check the compressor side of the turbo (intake side) and see if there is oil residue in there. If that is the case, you will need to run a catch can to keep that from happening. If that isn't the case, then we have other issues, and I need my other questions answered before I can let ya know.
 

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What is the color of the smoke when this occurs? Different colors will tell you exactly whats the problem, but yes worn seals may cause leaks.
 

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Discussion Starter #5
I need more information regarding the last turbo blowing. Was it just the seals or was there more than just that?

Also are you tuned to run more boost than 20psi?

Do you have any oil residue on the compressor side of the turbo or is that clean?

1. The exhaust side of the turbo seal being blown would cause smoking under boost as when you're boosting you're getting more oil pressure.

2. The breather line from the Valve cover to turbo can actually draw oil in from the valve cover/head to the turbo, this is why i said check the compressor side of the turbo (intake side) and see if there is oil residue in there. If that is the case, you will need to run a catch can to keep that from happening. If that isn't the case, then we have other issues, and I need my other questions answered before I can let ya know.
Car is bone stock, un tuned.
Previous owner overboosted the turbo & I'm not sure exactly if fins were chewed or what. (I know the guy who had it before, guy is a moron. Got a good deal on the car. Other than this issue, the car is amazing.)
I've had everything from a 6.0 GTO, to a H/C/I F body, to a couple built Srt4's, to a STI & so on. & to be honest this car is my favorite car I've owned. I really do love this car.

Anyway, there is some oil residue on the compressor side. This was after cleaning everything out & letting the car idle for a bit.
I'm losing very little to no oil as well. I've checked it frequently.

---------- Post added at 10:16 AM ---------- Previous post was at 10:16 AM ----------

What is the color of the smoke when this occurs? Different colors will tell you exactly whats the problem, but yes worn seals may cause leaks.
Its oil, lol.
 

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Levee
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Car is bone stock, un tuned.
Previous owner overboosted the turbo & I'm not sure exactly if fins were chewed or what. (I know the guy who had it before, guy is a moron. Got a good deal on the car. Other than this issue, the car is amazing.)
I've had everything from a 6.0 GTO, to a H/C/I F body, to a couple built Srt4's, to a STI & so on. & to be honest this car is my favorite car I've owned. I really do love this car.

Anyway, there is some oil residue on the compressor side. This was after cleaning everything out & letting the car idle for a bit.
I'm losing very little to no oil as well. I've checked it frequently.

---------- Post added at 10:16 AM ---------- Previous post was at 10:16 AM ----------



Its oil, lol.
Sounds to me like the vent line from the valve cover to the intake. That's very common for those to draw oil into the turbo. You can add a catch can and that will help the situation a lot. Most turbo cars have this issue, shoot, my evo had this issue all the way until I went Speed Density, so bacially it's any turbo car that uses the vacuum of the intake pipe to the turbo from the valve cover to help vent excess pressure for the PCV valve. I'd say change the PCV valve and put in a catch can and call it a day :)

---------- Post added at 11:51 AM ---------- Previous post was at 11:49 AM ----------

and you say the car is un-tuned.. How did the previous owner over boost the turbo if the factory turbo has an EBC on it that is bolted to the turbo itself? If he just unhooked that it would throw a code, and if he just put in a MBC, it would throw a code and I'd be questioning a few other things now too.
 

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Sounds to me like the vent line from the valve cover to the intake. That's very common for those to draw oil into the turbo. You can add a catch can and that will help the situation a lot. Most turbo cars have this issue, shoot, my evo had this issue all the way until I went Speed Density, so bacially it's any turbo car that uses the vacuum of the intake pipe to the turbo from the valve cover to help vent excess pressure for the PCV valve. I'd say change the PCV valve and put in a catch can and call it a day :)

---------- Post added at 11:51 AM ---------- Previous post was at 11:49 AM ----------

and you say the car is un-tuned.. How did the previous owner over boost the turbo if the factory turbo has an EBC on it that is bolted to the turbo itself? If he just unhooked that it would throw a code, and if he just put in a MBC, it would throw a code and I'd be questioning a few other things now too.
I pm'd you.
 
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