Saab turbo smoking on first start up.
Discussion
So, an update.
The car's certainly smoked less since I topped the engine up with 5/30 but there's still some smoke after I drive 100 ft or so. The smoke isn't immediate which is why I'm leaning towards the oil rings and not stem seals. I can't imagine rings or seals on all cylinders developing a simultaneous fault though.
Yesterday I changed the oil for a fully synthetic 5/30. The car definetely runs smoother. This morning after a 100 ft or so I had a lot more smoke then previously, with the the 15/40.
I'll have to wait and see what happens over the next week or so.
The car's certainly smoked less since I topped the engine up with 5/30 but there's still some smoke after I drive 100 ft or so. The smoke isn't immediate which is why I'm leaning towards the oil rings and not stem seals. I can't imagine rings or seals on all cylinders developing a simultaneous fault though.
Yesterday I changed the oil for a fully synthetic 5/30. The car definetely runs smoother. This morning after a 100 ft or so I had a lot more smoke then previously, with the the 15/40.
I'll have to wait and see what happens over the next week or so.
GreenV8S said:
Is it possible the turbo is seeing too much oil pressure when the oil is cold, and it is blowing past a seal?
I did think it was a turbo seal Peter hence swopping the turbo. Now it's either duff rings on all cylinders (unlikely), an oiling issue/pcv, or a stem seal. The engines transverse, canted forwards towards the exhaust side but oil had good drain back to the sump. I'd be surprised if the valve stem seals are submerged in oil. I'll have to remove the cam cover if nothing improves.GreenV8S said:
Boosted LS1 said:
I did think it was a turbo seal Peter hence swopping the turbo.
Have you checked the oil supply and return line restriction?The oil supply is unrestricted and the drain pipe is 1/2" dia. I'm going to park the car on the tilt for a few nights to see if that drains the oil away from around the valve stems. I'd be surprised if they're submerged in oil once the engine's been standing for a while but it's an easy test. I can also loosen the exhaust header and look for oil the following morning.
The symptoms you describe sound to me like a knackered turbo. I had a “good” second hand one fitted to mine and apart from a strange whirring noise, it was also down on boost and gave and oily exhaust. Failed spectacularly with clouds of white smoke so had a brand new one fitted and it’s transformed it. I think second hand turbos are a false economy personally!
Have you tried fitting a boost gauge to see what the turbo is doing?
Have you tried fitting a boost gauge to see what the turbo is doing?
^Thanks, It doesn't have a boost guage but I intend to fit one. The turbo was replaced with one that I used on a former engine. The car pulled better after the replacement but feels 'normal' now. The turbo hangs underneath the exhaust header and I have seen oil on the mounting flange, ie above the turbo cartridge. I'll take a closer look at the turbo I removed.
What sort of Saab is it? If it’s 2.0 9-5 or late 9-3 it’s likely running T7 ECU which controls boost, spark and fuel. Quite normal for it to adapt to a hardware change so it feels “normal”. However these things do eat turbos it’s quite normal for one to limp along until it seizes or fails altogether, pissing oil as the seals disintegrate. Fitting a gauge, even temporarily is a 5 minute job, you can tap into the vac hose on the top of the manifold, on the back of the engine. Great for diagnosing boost issues. Good luck!
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