I just bought a 98 s70 GLT and it smokes badly. I was told that the turbo was bad. Does this sound likely, or is it valve stems seals, rings, etc.

 

I would make sure the vent system isn't clogged.
The I would inspect the turbo.

 

I doubt it's the valve stem seals since it smokes all the time, not just when cold or maybe the volvo s70 radiator.. If you have low compression on one hole pressurize it with compressed air and listen to the intake, exhaust and crankcase vents to see if you can hear where it is leaking from. Can't really tell if a valve is burnt or carboned up without pulling the head, but if it has been sticking open for awhile it is probably burnt. Perhaps your turbo seals are leaking?..

 

Here is what I find on a lot of Turbo models. Oil change intervals are too long at 7500 miles for a turbo in my opinion. The dirty oil leaves deposits in the drain tube from the turbo to the oil pan and eventually clogs causing the turbo to fail. We recommend all Turbo models get 3000 mile oil changes at our dealer.

I replaced 4 turbos on different models and all of them were from the oil return or supply line (or both) being clogged.

 

If you could specify the colour of the smoke, we can help you better but in this case it is probably bluish-undeniably-engine-oil kind of colour, right?

If so, follow the above gentlemen's advice.

I 100% agree with Johnny's opinion on oil change interval for turboed engines. The most important maintenance for a turboed engine is oil management. Using high quality oil (synthetic/synthetic blends are highly recommended) with OEM filter is imperative, as well as changing them at every 3,000 miles/4,800 kms.


JPN

 

i couldnt agree more with JPN...i only use Synthetic Blend with OEM filters...it makes a world of difference. Especially in a turbo.

(its nice to see that there are knowledgable people on this forum)

PS...did you buy the car with the smoke problem already? or did it just start?