About to order new turbo but have to ask about blue smoke from car first

[Lord Khan]

About a month and a half ago I started to notice a light puff of blue smoke coming from my car intermittently when pulling from a stop. Now, that puff is coming out anytime I hit the gas hard and the boost goes over 11lbs. My T25 is at 106,000 miles (top that!) and I drive my car hard, so I'm impressed it's still going. My question is, would leaky turbo seals cause the oil to come out like that for sure, or is it possible that it's valve's leaking, or leaky piston rings.

I know it seems almost obvious that it's the turbo, but I didn't have time to do a compression test this weekend, and just thought I'd ask for the hell of it. I've been testing the car out for the past week by driving under boost, and also boosting. The car still feels very strong, and when I crank up the boost, the turbo can still spike at high boost levels (17PSI) when cranked high. When driving under boost, no smoke comes out, but when I sit at a light for a few minutes, then accelerate, and floor it quickly, a bit of smoke will come out steadily from the tailpipe very lightly (I had a friend follow me to check), and soon as the BOV sounds, a bigger puff of smoke comes out, and also when I shift.

Do you think for sure it's probably the turbo, or what? I'm at my desk at work, and I'm about to order this BigT28 from Forcedperformance.com, so I just wanted some advice before I make this kind of investment.

 

[Mackzero]

Sounds like your turbo to me, have had a couple buddies whose cars did the exact same thing when their turbo was near it's end.

 

[Lord Khan]

Yeah, I'm almost sure thats definately what it is. But just wanted some of the more experienced opinions from here.

 

[Lord Khan]

Big T28 ordered from Forcedperformance.com. Wish me luck. Can't wait!!!!

 

[Spidey]

You said it doesn't smoke under boost, and that it puffs smoke after sitting stopped at a light when starting off. This leads me to believe it's the valve stem seals. My car did this with the T25, and now with the 14b, so I know it's not the turbo. It has also gotten worse as time has gone by, it used to only smoke after sitting stopped for a few minutes, now it just smokes all the time. Don't be so quick to blame the turbo, it's probably the valve stem seals.

 

[Syndicate13]

If it was still boosting fine then it most definitely wasn't the turbo. When my friends went out it wouldn't build more than like 6 psi and made a god awful noise when it did. Eventually the shaft play got so bad the turbine wheel dug itself into the turbine housing and that was the end of that.

 

[Lord Khan]

I don't think the turbo is blown, I think the oil seals are leaking. My friend and I noticed some very slight play in the turbo almost a year ago, and like I said I drive the car HARD. I knew it was only a matter of time before I'd start to kill the T25. Either way, a new turbo won't hurt. If it is the valve seals, then I'll just have to replace those as well.


BTW, when it smokes from a stop, it only does it if I floor it, and build boost from a stop. Sorry I wasn't clear about that in the original post. I've been driving for the past week and accellerating without boosting, and it doesn't smoke at all. If I'm on the highway, and driving under boost, then floor it and boost high, it will puff smoke.

 

[telly699]

Blue smoke usually occurs when oil is entering the combustion chamber and is burning along with the fuel. Possible causes include valve seals or cracked piston rings. You say it doesn't smoke at all when not boosting? Are you sure you just cant see it? If that is the case it may be the turbo. (turbo leaking oil that is burning?) Try a compression check so at least you can rule out rings. Then if you wanted a turbo, go ahead and get it. It cant get hurt... i dont think. If the smokes gone, it was the turbo. If it isnt it is probably the valve stem seals. Good luck on this, or if you wanted, you could just keep it in case you need to pull a daring escape from that persuing clan of Mid-Eastern terrorists your always running from.

 

[ITSME4G63]

would this have anything to do with the turbo? When I hit WOT, when I just get on the highway, I gun it until about 85 and I let off the gas, I saw some amounts of smoke going out my exhaust pipe as I looked in the rearview mirror, shit was kinda tight when you think about it, I was like, Ohh that guy way back there got owned by my cars fart

 

[Lord Khan]

"Blue smoke usually occurs when oil is entering the combustion chamber and is burning along with the fuel. Possible causes include valve seals or cracked piston rings. You say it doesn't smoke at all when not boosting? Are you sure you just cant see it? If that is the case it may be the turbo. (turbo leaking oil that is burning?) Try a compression check so at least you can rule out rings. Then if you wanted a turbo, go ahead and get it. It cant get hurt... i dont think. If the smokes gone, it was the turbo. If it isnt it is probably the valve stem seals. Good luck on this, or if you wanted, you could just keep it in case you need to pull a daring escape from that persuing clan of Mid-Eastern terrorists your always running from."


Yeah, I went ahead and ordered the turbo already anyway. Whether its the T25 smoking or not, I don't trust it for the way I drive, so its getting replaced first (bonus check from work) The Big T28 from FP should be here next week. I'll know then. I'll post up results. If the problem persists, I'm going to have to go into the motor.

 

[telly699]

yes you will.

 

[ChicagoGSX]

The easiest way to check if it is in fact the turbo is to remove the LICP. If there is oil in it then it is the turbo. If not, do a compression test. If adding oil to a cylinder raises the numbers then it is your rings. If neither of those happen, then it is your valve stem seals.

 

[Lord Khan]

Update.

While I still haven't done a compression test yet, I finally found some time yesterday and took my intake off to check for play in the turbine wheel.

Is the turbine supposed to move in and out a quarter of an inch when I push and pull on it?! ! :laugh:

Yeah, my turbo is at deaths door. Hopefully this is the primary source of my problem (how could it not be at this point). Anyway, thanks again for the advice guys.

 

[blackGSX2g]

yea, actually my t-25 is doing the exact same thing...I can't boost over like 5psi without some light smoke, and it won't hold any boost above like 10psi, it jump around and make baaad noises. Also, the biggest plume of smoke is right after I shift too, and I tested compression not too long ago and all 4 were around 180psi, so I would assume its just your turbo. Post a reply when you get the new turbo put to just so I can rest easy as well and know the my new E16g will not be but to waste on a bad engine

 

[Gooberlog]

It appears that any 4G63 engines over around 100K may start smoking out of boost from a light due to hardened valveseals. For your stock garret turbo to last that long is pretty good. Since you already have your upgraded T28 on the way, i would say install it and see how your car boosts and watch for the smoke. Have a friend drive behind you around town and watch for the smoke from stop signs and cruising and boosting down the road. If the smoke is still there when leaving a stop sing/light, its likely that its your valve seals. If your valve seals need to be replaced like mine did and my friends does, you'll have to remove the timing belt and pull the cams out etc. If you don't have anywhere to do this work or don't have the propper tools, feel free to email me or send a PM, i live in Howard County MD and i'm a Mitsu tech that can do some sidework at my house. Good luck.
Travis