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Saab 95 blue smoke from exhaust

I have a 2001 Saab 95. For about a year now, when I cold start the car I get a good size puff of blue smoke from the exhaust. I took it to a trusted mechanic. He took the turbocharger apart to look for oil leak. Found nothing. He changed the oil and put in an additive. That worked for a day or two then it started smoking again. I called him back. He said it could be a valve/ring/ problem and depending on exactly what it is, it could take a couple of days to repair or worst case they would have to take the engine out and it could take a couple of weeks and cost a couple of thousand. Is he on the right track? Should I go to a dealership? I checked the oil a couple of days ago and it is not low. Any advice? Thanks Mark E

I do not understand why he would take the turbocharger apart unless there is a misinterpretation here. Maybe he did not take the turbo apart but simply removed some of associated ducting to see if it was oily inside; which would be a sign of leaking seals.

The first step on a complaint like this is to run a compression test and possibly a leakdown test. One can verify (with a high degree of probability) if a piston ring problem exists or not.
Valve seals can cause this and there is no test for valve seals. Regarding those, one has to replace them and hope that cures the problem.

I hope this mechanic is not saying they may have to pull the engine and go on a fishing expedition. That’s the inference I get from your post and if so, he is not on the right track. At all. Hope some of that helps.

I also wonder about your mechanic. First thing I’d think of would be valve seals, not turbo, and I’d do what OK recommends. May be time to seek out another mechanic…

ok,
Thanks for the info. If it is a piston ring or valve seals how much could I be looking at? What’s the worst case scenario for my engine if I just keep the oil level up?

Thanks again

Thanks for the reply. Another mechanic or a dealership?

Well, the things that need to be done next (see OK’s note) don’t require a dealership. Have you used the ‘mechanic finder’ under ‘Actual Car Info’, above?

And my '96 ES300 does that ‘little puff of blue smoke’ first start in the morning, has for 6 years, and I don’t plan to fix it, it runs fine otherwise and uses very little oil. How many miles do you go between adding a quart?

Any shop, dealer or independent, can run a compression or leakdown test. That should be the first step. On average, an independent is usually cheaper.
If this is done, you might consider posting the results back here for discussion. There seems to be a large segment including mechanics who seem to think that low readings are actually fine ones. To make things even worse, many service manuals are also incorrect in their specifications and not just with compression readings.

If this is a ring problem then you should back up and take a deep breath. This generally means an engine overhaul.
Valve seals can be replaced without too much disassembly. This can be done with the cylinder heads in place and while it’s an involved process is really not that bad.

Blue smoke means some oil is getting into the combustion chamber. It can come from the bottom up by getting by old tired rings, or it can come from the top down by leaking and getting past the seals in the valve guides.

If the compression check shows all cylinders are fine, then it is most likely coming from the top of the motor via the valve guides. Replacing valve guide seals isn’t as major as all new rings (which means a motor overall). But, it is still going to be expensive on a Saab.

Could oil get past the turbo seals and burn enough for blue smoke? Perhaps; but this would not be a puff of blue smoke upon start up. It would be continued blue smoke after the car warms up.

Worn rings aren’t very like to be the “puff” at start up either. Worn rings is a puff of blue smoke when you get back on the gas after a period of deceleration, ie. going down a hill and then getting on the gas to go up the next hill.

If it is just a puff at start and you are not adding more than a quart of oil every 1,000 to 2,000 miles this might be just something you live with and now a characteristic of your “getting older” Saab.

You should have you PCV valve and crankcase ventilation system checked out to rule out any clogs, cracked hoses, or misplaced hoses and vacuum lines that could cause smoking.

T,

I have been getting the smoke for a good year. I would usually just get the oil changed every 3-5,000 miles. Besides that, and a few other little non-mechanical things that are breaking down from old age, the car has been running fine. Thanks again for the help

OK,
Thanks again for your help. I will look into a compression or leakdown test. First things first. I will let you know on this posting what happens or ask what I should do next. Win the lottery so I can just go out and buy a new vehicle.

While you’re at it, find out what the “additive” the mechanic put in the oil was. If it’s an oil thickening agent or some sort of stopleak, get the oil changed now. Turbos don’t like doctored oil.

Not a turbo, that ‘t’ is for ‘touring’, as in suspension.

“He took the turbocharger apart to look for oil leak.”

Turbo :wink:

OOPS! Nevermind, my brain was stuck on the Infiniti G20t thread - you’re right - turbo it is!