My 2007 S60 2.5T (78,000 miles) occasionally emits grey-white smoke out of the exhaust at startup -- probably about 20% of the time. I understand it could be a turbo issue but any other simpler/cheaper explanations I should explore first? Any remedies I should try? Thank you.

 

is the car consuming any oil? (ie do you need to add a quart between oil changes or top the antifreeze from time to time?) I'd probably suspect this is really condensation from the exhaust pipe. Also keep in mind the car automatically enriches the mixture (like a choke) during start up which can leave some unburnt fuel for a few seconds to pass through the exhaust. Are you running synthetic or dino oil?

 

Thank you for your quick response! I did recently need to top up the oil by about 1/2 quart but it has not gone down since and there was no smoke until about a month ago. Smoke seems to be too light for oil smoke. No loss of coolant at all. It has been some time since my last oil change (5,000 miles or so) so I am doing a change tomorrow myself with synthetic. I am pretty sure the last change was dino oil. Thanks.

 

Grey white smoke is typically an indication of coolant in the combustion chamber.

Check out this:
Exhaust Color Diagnosis | White Smoke Blue Black

 

[QUOTE=gatorbrit;413209]Grey white smoke is typically an indication of coolant in the combustion chamber.

Thanks for the response. Since posting the smoke has gotten worse and after a 20-minute drive the smell of the smoke was unmistakably like a candle after it's been blown out, not sweet like coolant at all.

I examined the air charge tube and it was clean, as was the compressor side of the turbo. At a loss, I ended up taking the car in to a highly respected/recommended independent Volvo mechanic. He has diagnosed it as a blown turbo, says oil is leaking into the exhaust side. Also says my PCV system is sooted up and should be replaced. He was shocked that the turbo is bad, said he very rarely has to replace them. I've been good with oil changes since we bought it (4 years ago when it had 48,000 miles on it) but he said neglect even by the previous owner can take years to manifest itself. He also said that while extremely rare, some turbos just go bad all on their own.

So it's at the shop right now and should be repaired by the end of the week.

For what it is worth, this mechanic (30+ years experience with Volvos) had some wisdom to pass along:

- He strongly recommends using Castrol Syntec and replacing the oil at no more than 5k miles.
- He said that Royal Purple is also good.
- He said that XC-90s are "hit and miss" and should be avoided. He "hates them".

 

turbos do occasionally need rebuilds when the seals go - but this is more common on the 850Ts/S70s with high mileage and suspect maintenance histories. The fact that he is suggesting the PCV system is gummed up points to poor oil maintenance from a prior owner but I'm really surprised about this happening at 78K miles, if you decided to convert from dino oil to synthetic, some people suggest a Seafoam treatment (or similar high detergent oil additives), prior to replacing the PCV/oil trap but best to do your own research. Note that some turbo models have an oil return line gasket that can fail and put oil all over the place including your garage floor... Totally agree that any newer Volvo should go on synthetic oil - older Volvos are hit and miss as the older seals can harden and synthetic being more slippery can leak... (thus my 850 is on dino and my s40 on synthetic). If you wind up replacing the turbo as a unit, collect your old one if you can and sell it on eBay or the Volvo board - somebody will be happy to rebuild it and use it in a project.