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Discussion Starter #1
Here is what happens:
1. Engine at running temp.
2. Stay at idle for 2 or more minutes
3. On acceleration, will get spark knocking and oil burn as white smoke from tailpipe.
4. After it is burnt off, no more smoke, no more knocking. Until at idle again for said amount of time.

Here is what I have attempted to fix/diagnose:
1. Swapped the turbo. Garret for TD-04. Old turbo was good condition.
2. Checked the brake booster for oil. No oil.
3. PCV update kit was already installed so that shouldn't be a problem. Should I check the oil trap?

Been having this issue with the 2000 9-3 convertible for many months now. Recently, when I talked to a friend of a friend about it- He said emphatically that it's a head gasket issue. Although he may be right in his quick assumption, the common tell tale signs of a blown head gasket are not apparent i.e , temp fluctuation ,overheating , contaminated oil, loss of coolant.
Right now I am taking his opinion into serious consideration because I am having to weigh my options with this car. With all this oil burning after this amount of time, that means a possibly ruined catalytic converter. Not so good news for getting emissions testing later this year. With all things considered, I'm weighing my options for the right thing to do.
 

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What do all of the plugs look like, is one or two worse than the others? Do a compression test.
 

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Are you sure its not loading up on fuel while idling? Bad fpr.

Are you having to refill oil every week, month etc....
 

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Discussion Starter #5
Not sure why I just now noticed, maybe it is hard to tell the difference, but I took a video and the smoke is more of a blueish grey color. ;)
Have to put in oil every two weeks or so.
Will check the plugs this evening and report back after engine cools down a bit.
thanks

Here is the video, for what it's worth
https://youtu.be/syfhS11pkiA
 

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I'm just going to throw this out there but if your not seeing any cross contamination between oil and coolant then it might be a broken compression ring after letting it run pull off PCV or oil cap to see if any smoke is bypassing the piston and into the block. A compression check will confirm which cylinder is the culprit
 

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Discussion Starter #7
Might be able to get a compression check tomorrow. My dad aught to have something for that within his vast array of tools.

So, there is something serious going on in cylinder 4. Some major carbon build up on that spark plug. Replace about 5 months ago, approx 5k miles..
Attached are images of spark plugs 1,2,3,4 respectively
 

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Ok then, probably is blue/grey smoke, but only noticeable after an extended period of very high vacuum in the intake.

How about this: at idle, oil is being sucked into the intake manifold and on acceleration, the oil is then swept into the combustion chambers causing poor ignition and the smoke.

Once the oil has "blown through" overt symptoms vanish until another period of idling.

The "odd" bit is where the oil would come from in the first place.

Wondering if the engine driven vacuum pump has failed and allowing oil to flow from the pump, into the brake booster vacuum line and then into the intake.

Other possible candidate is the PCV system, but I'm not sure it could pass enough oil rather than oil vapor into the intake to cause the symptoms.
 

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If your dad doesn't have a compression tester don't sweat it there only like 30$ and I'm willing to bet whatever is going on you will be able to figure it out with a cheap tester because your undoubtedly have to be loosing compression somewhere. Are there any other signs of engine wear like loss of power, fluctuating idle and engine noise?
 

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Yeah. It looks like your in for a rebuild. If oil were being sucked into the intake mani all the plugs would be crusted.

Honestly I would just look for another Saab to buy and keep yours as a parts donor. They are cheap enough.
 

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If oil were being sucked into the intake mani all the plugs would be crusted.
Not sure that's necessarily true, remember, the vacuum source for the brake booster is directly behind the intake runner for cylinder #4.

It'd be an easy test: Pull the vacuum line off the intake, plug it, start the engine and let it idle for a few minutes. See if the issue recurs -- just don't forget the brakes might be a very stiff if the booster looses vacuum during the test.
 

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Thats possible. But honestly i bet the rings are shot #2 plug is the only good looking plug. I bet previous owners ran dino oil, never changed it, smoked the rings and the pan drop and new synthetic oil were just to late. OP bought a lemon. It happens.
 

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I have to agree with mdo if the vacuum line was compromised to the extent that oil was making its way through the the brake booster I doubt he could idle at all not without feathering the throttle but I like preparing for the worst case senerio. But It might just be a stem seals
 

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Discussion Starter #15
Results of the compression test:
(Dry number is first)
#1. 130 190
#2. 140 180
#3. 135 190
#4. 125 170

That doesn't seem to indicate any issue with a head gasket. Looks like #4 is holding a bit less compression, but they all go up considerably with the wet test. Engine is wore out. :cry: Only had it for 6 months, but the smoking only started when I changed oil for the first time. Still a bit perplexed about how the oil gets thrown in there at idle like it does.
 

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Discussion Starter #17
Just an update to anyone in case it helps.
My saab stopped smoking all of a sudden. I cant say exactly why or how. I chamged the oil 6 weeks prior to the issue going away. With shell rotella. And some kind of stop smoke additive in a small silver blue can i cant remember the name. Every time the dipstick was low i added lucas. Then, my fuel pump went out about a month after the oil change. Replaced that, then I got some codes for an 02 sensor which got melted against the exaust. At about that same time, it stopped burning oil and smoking. I am confused but relieved this problem seemed to resolve itself with no apparent reason why.

Sent from my LG-H811 using Tapatalk
 
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