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Discussion Starter #1
Car has 96k. Compression pretty much 196 across the board. I have not done a leak down. I'm burning way to much oil, especially now that its getting colder I get way more smoke on startup. I don't see much, if any when its warm, but I bet it's burning some, just cant see it. Unfortunately I only drive this car short distance which I know hasn't helped the motor. I pulled the DP, shaft play seems very mynute. There is a nice coking of black carbon on hot side. I do not see any visible signs of wet oil sitting in the hot side, not sure I would unless seal was shot. I fired her up with DP off and it pretty much immediately started to smoke (blue). This was about 5-10 seconds after it fired. I let it idle for only about 10 seconds more max, still smoking, shut her off and pulled the plugs. There was no oil contamination that I could see. Now, what I was hoping for was that there was going to tell-tale signs that it's the turbo, but I'm guessing it's not. Why, and pleaaaaaaaase correct me if I'm wrong, but I would assume that if I fired the car up after it sat all night with dp off that I would not see blue smoke right away coming out of the hot side because really, 'I would think' that it would take more than 10 seconds for the turbo to get hot enough to burn it.
Any help would be greatly aappreciated form people who have way more experience.
Thanks much!
 

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Finding the source of oil can be difficult on turbo motors. A blocked PCV system can cause excessive consumption, leaky valve stem seals are on the table (although with low mileage it's unlikely), blowby is on the table (although with good compression it's unlikely), and of course the turbo.

A blocked PCV system can have various effects, but tends to be worse under boost. Generally smoke on startup or major throttle transitions (atom->vacuum) is leaky valve stem seals, but TBH I have NEVER had that problem on a Saab. Blowby tends to be a problem under boost. The turbo tends to be worst at idle.

With nothing else to go on, I'd suspect the turbo. You can isolate out the PCV system, you can buy a friend a beer and do some snap tests... but short of a (blue) smoking gun it'll be difficult to know for sure if it's the turbo given the symptoms you have. Maybe have that same friend - two hours later - follow you around and watch the tailpipe to see if it shows up at other times?

Edit: I suppose it could be a just so head gasket failure, but I've never experience that scenario, either.
 

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Discussion Starter #3
Thanks for the info. I retorqued (replaced) the head bolts a few months ago. Zero sign of any being loose. Yeah, it could be a head gasket, but this has been getting worse for a few years now.
I know the shaft doesn't really have to have much play if the oil ring is bad.
I replaced the white pcv valve a few months ago even though the old one was fine. I checked the hard line going to the cobra, could not see any oil at bottom of cobra pipe. I hardly get any blow by, all other pcv lines look okay as well.
I let it sit, fired it again and I'm almost positive I saw oil spurting out and burning almost immediately within the housing for the first 15 seconds. Its pretty amazing how fast it gets hot. But really, I might have been imagining it. Going to fire it again later and use the good ol white paper trick in hopes I see oil spurting out on paper.
I have had cars with bad valve guides/seals, but I cant see any smoke when I let off it.
I had a turbo let go on the freeway once, zero signs of any smoke, lack of power, etc. It just up and snapped the shaft, locked up and billowed smoke like no ones business. So much that someone called the epa, or whatever and I received an email 3 weeks later about it.
If I see any oil on the paper next time, I'm just going to pull turbo and rebuild it. At least I can then rule out turbo if it still smokes.
 

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After everything you've said I would narrow that down to the turbo but I wouldn't rule out the valve seals and guides. And a leak.

Have you looked inside your charge pipe for oil?
Oil in the charge pipe could be from the turbo or from the pcv or both.
 

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Discussion Starter #5
Charge pipe was the first thing I have checked, over and over. There is no discernable oil in any pipe, that's why I have mixed feelings that it's the turbo.
 

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Charge pipe was the first thing I have checked, over and over. There is no discernable oil in any pipe, that's why I have mixed feelings that it's the turbo.
That leaves the valve seals and guides.
If it were the oil rings vapour would come out the pcv and end up in your charge pipe too.

It's pretty much the only thing left.
Have you identified which cylinder it is by checking the spark plug?
 

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Discussion Starter #7
All plugs look fine, even after I shut it down right after I fire it and when it smokes.
 

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All plugs look fine, even after I shut it down right after I fire it and when it smokes.
Probably so little actual oil gets on the plugs.
Leak down test for all the valves it is then.

At the risk of telling you how to suck eggs:
Take the cam cover off.
Select a cylinder and rotate the engine 'til the valves are shut.
Inflate the cylinder using a tool you just made out of a spark plug and shraeder valve.
Do a "soap bubble" test around the valve guide.

If anyone has an easier way I's like to hear it.

You could also strip the valve assembly using one of those tools that allows you to do so without taking the head off and wiggle the valve in the guide.
Run the piston around to TDC so the valve doesn't fall into the cylinder.
 

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Discussion Starter #9
Yeah, suck eggs! lol. Time for a leak down. I was going to just pull the turbo and send it off in hopes that this is the issue, but nah, I guess. Ugh!
 

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Flash - I'm not sure that's a valid test. With the valves shut, there is no access from the CC to the valve stem seals... the valves should be sealed against the seats. If air is getting past the guides/seals at that point, you have a (much) bigger issue with valve or seat.

AFAIK, there is no way to conclusively diagnose valve stem seals except by symptom - leakage during periods of high vacuum, such as on start. Hot oil (thinner) makes the problem worse. There are a number of tests that can be run here - cold start -> 2000rpm, hot start, snap test. But not air in the CCs.

LMS: Turbos can fail into the exhaust side too. IME, that's the typical way old Garrett T3s on c900s would fail. Once day you'd pull up to a stop and a cloud of blue smoke would go wafting by. Rarely would there be oil in the intake.

FWIW, none of these jobs are The Worst. Although doing valve stem steals does require being able to pressurize the CCs.... A leakdown tester is a great way to do that. I have used this tool:


for doing seals on other cars. I think would work on a Saab, but I've not tried it. The keepers on my Hyundai were two piece like a Saab and it worked GREAT. I did all 16 in about 90 minutes. The timing chain is a bit more of a hassle than the Hyundai's timing belt, but not by much. :)
 

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Discussion Starter #12
Hmmm, what to do. I still have the DP off which is 1/4 of the battle in regards to just pulling the turbo. Valves are a whole nother shebang.
Yep, my T3 did that back in the day.
 

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If you're going to pull the turbo, comparing the exhaust inlet to outlet for oil should give you a really reliably clue where the oil is... before or after the turbo.

For a valve stem seal check, I bet you could remove the valve cover and pressurize the whole intake using an intake leak detector fitting, then rotate the engine around to get one cylinder intake open + exhaust closed at the same time and listen for leakage on top. It would be a bit annoying, but probably fairly conclusive.
 

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Flash - I'm not sure that's a valid test. With the valves shut, there is no access from the CC to the valve stem seals... the valves should be sealed against the seats. If air is getting past the guides/seals at that point, you have a (much) bigger issue with valve or seat.
You're right, I shouldn't try to think in the middle of the night.
 
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