Turbo "seals"

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I wish there was a straight forward answer to that. It will likely continue to smoke until all the residual oil is cleared from your Intercooler and charge piping.

Also, it may not solve the issue at all if that is not the culprit to begin with. Thus is the frustration of troubleshooting.

The best I can do is tell you what I would do, if I was in your situation. Start with anything you can that doesn't require spending money to chase a problem you haven't confirmed.

Again, it sounds most likely that it is a PCV issue.

First place to look to help confirm is the PCV entry into the cold side of the turbo compressor. Remove the air intake piping that goes to the top of the compressor and look down in there at the ~1" hole where the PCV enters the housing.

If you see evidence of large amounts of oil having poured down from that hole..... You are confirming a PCV issue. At that point, I'd be more inclined to assume the valve cover diaphragm is suspect.

 

[6spdsonic]

Putting new valve cover on now. There a lot if residue in the intake side.

 

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Hopefully that does it. Like I said, you still may get smoke from residual oil from the intercooler. But it should slowly clear up as you rack up some mileage.

Let us know how it goes.

 

[sx sonic]

Putting new valve cover on now. There a lot if residue in the intake side.

Are you having this replaced under warranty, or just throwing parts at the problem?

 

[6spdsonic]

Putting parts on it. I can't take it to the delarship bc it's been tuned. So they'll see that and void warrenty.

 

[Preloader]

Putting parts on it. I can't take it to the delarship bc it's been tuned. So they'll see that and void warrenty.

Patently untrue. Read the Tune threads.

However, for inexpensive repairs, I'd much rather DIY than go through all the headache of restoring to stock and then having to arrange a day around turning my car over to a take-their-sweet-ass-time dealership.

 

[sonicR]

Unfortunately I am doing that exact thing. I took it to the dealer they changed the seal in the crank case. After going to work and back 100 miles still smoking a cel appeared. Its back at the dealership. I noticed that its losing boost. Highest is about 5 lbs. I wonder when the tech is going to realize that the turbos gone out. I only mentioned it about 4 times.:blankface:

 

[sonicR]

Man... are there any good techs know days? Wtf. Got my car back last night. Everything appeared to be ok. 2 miles later the cel came back on. The service tech said that the changed the unit. I checked the oil and no oil in the car. And the car is still reaading p0299. Im looking into the pa lemon law. This is unacceptable. Gm techs suck!!!!!!!!!!!!!!!!!!!!

 

[Chevrolet Customer Care]

sonicR,

I am sorry to hear you are having these concerns with your Sonic and dealership. I would like to look into this further. Please private message me your name, VIN, phone number, and dealership.

Erica Tiffany
Chevrolet Customer Care

 

[6spdsonic]

got a stock flash on the car and replaced the valve cover and still smoking when i decel after being in full boost for about 10 seceonds.

 

[6spdsonic]

Cars still smoking on decel. Did a compression test and it's fine. No leaks nothing. Next is going to buy a turbo.


Sent from my iPhone using Tapatalk

 

[Preloader]

It's not likely the turbo. Several have replaced the turbo, chasing the same problem you're are experiencing and it did not solve the problem.

There is an oil separator orfice in the PCV system that is located in the intake manifold. I'm trying to investigate this puff of smoke problem more, since it seems to be becoming an epidemic.

It keeps leading me to the PCV system. It may be a matter of replacing the intake manifold.

If that is the case...... Even though a new IM is expensive, it is much less than a new turbo.

 

[stealth]

Anyone ever figure out the puff of smoke thing. At the dealer now with this problem they say its the turbo.

 

[mja]

To post a reply about digging up this old thread. I believe the turbo ring seals are being stressed when some pcv components go out. This is one reason why the dealers are replacing turbos on stock setups. Others have had crank seals go or other bottom end components.

Unfortunately if the infamous cloud of smoke is happening, the PCV system is suspect and the most complete course of action is to replace intake manifold, cam cover, and PCV turbo inlet valve (the corrugated tube) all at once. I guess you could troubleshoot and piecemeal it to save money. If the turbo is still passing oil through the compressor, that should be replaced too.

The dealer should cover all of this under warranty. It seems a lot of times they don't replace the intake manifold or turbo inlet check valve, or some techs didn't get the memo that there are other weak links in the system. So they replace turbo and cam cover, and the problem comes back or happens again.

 

[JesusTheAgnostic]

I thought the turbo was supposed to pass oil through it. Before I ever had anything go wrong with my car, when I installed the intake I swear I saw some oil on the inlet tube to the turbo.

 

[mja]

I thought the turbo was supposed to pass oil through it. Before I ever had anything go wrong with my car, when I installed the intake I swear I saw some oil on the inlet tube to the turbo.

Oil is fed to the bearings yes, but it shouldn't be coming out your exhaust

Edit - JTA... the oil in the inlet tube is the start of the problem. That could indicate a faulty check valve in the intake manifold, or the cam diaphragm could be blown. If these aren't replaced, the problems get worse.

 

[mja]

On second thought, the turbo has coolant passages for it. I wonder if the 'disappearing coolant' issues are from similar problems. Hmm.

 

[JesusTheAgnostic]

O:! What does it all mean! I don't think I have a lot of oil, but like Llia showed the pictures on her thread, that's how my stuff looked. Though I didn't check all that until after the suicide disk broke, and after the engine swallowed the orange valve. What I do remember though is that the inlet to my turbo had what looked like dried oil on it. I'd have to take it apart again to see how it's doing.

As far as I know though the engine isn't burning oil anymore. Not since replacing the intake manifold.

 

[mja]

O:! What does it all mean! I don't think I have a lot of oil, but like Llia showed the pictures on her thread, that's how my stuff looked. Though I didn't check all that until after the suicide disk broke, and after the engine swallowed the orange valve. What I do remember though is that the inlet to my turbo had what looked like dried oil on it. I'd have to take it apart again to see how it's doing.

As far as I know though the engine isn't burning oil anymore. Not since replacing the intake manifold.

Yes, you should be fine after replacing intake manifold and diaphragm. From my understanding at this point, if that orange check valve goes which supplies a vacuum bladder to the bypass valve, then the turbo has no way of relieving pressure under low intake vacuum (at wide open throttle). That bladder holds vacuum so the BPV can do its thing under all engine conditions. Similar to how a brake booster stores vacuum for your brakes, at least this is how I think about it.

If the check valve goes, or if the BPV has no vacuum to operate it, this means the turbo compressor could surge at less than ideal times. Some turbo experts can help out here, as my knowledge is lacking in that area. It seems this orange check valve is associated with the PCV system, although I'm not sure anyone is 100% on what conditions cause it to blow out. So a number of problems occur at once due to the PCV, and all of these problems can be mixed together or isolated depending on the case.

It seems the most common problems due to the PCV system are:
1) oil on the cam (valve) cover after blowing the rupture/burst disk. this can cause a faulty ignition coil and misfiring
2) Orange check valve disappearing, this seems to directly affect the BPV, and could cause compressor surging and stressed turbo bearings, etc
3) pressurized crankcase, could blow out a number of things on the bottom end due to oil being wiped out from bearings or forced out of seals, it could also starve certain bearings of oil - crank/main seals, accessory gaskets, ring seals, etc.
Edit - 4) oil in the intake inlet, ranging from small drips to a flood

Someone could review this, there may be some incorrect info in here, but for the most part this is what's happening when PCV components go.

 

[JesusTheAgnostic]

I know I forgot to shift, then heard what sounded like an electrical fire and that's when my little orange valve went. I hit 6.5k RPM. Also anyway you could explain what turbo surge is? Because that's what Jerry said the problem was with my car, now he's tuned it differently and is slowly adding more power again.