We own a 1998 Volvo V70 (AWD) with 145,000 miles. The breather box was recently replaced (because the mechanic suggested this should be done). I should mention that before this work was done, the car ran fine. Absolutely no problems, but we took the mechanic’s advice figuring it was the prudent thing to do. About a week after the breather box was replaced, we noticed that the car was leaking quite a bit oil. Because the car never leaked oil before, we figured the problem was related to the recent breather box work. So, we took the car back to the mechanic and had him look it over. He changed a small hose, saying that it had been clogged with carbon. He also dumped some oil additive (Seafoam) into the system in the hopes that it would break up any other bits of carbon, which would then work themselves through. The car was ok for a couple of days. Then, following some freeway driving, voluminous clouds of nasty blue smoke started coming out of the exhaust. We took the car back (again), and the mechanic again checked the hoses leading to/from the breather box, and he again dumped in Seafoam. He noted that there was high positive crankcase pressure. We took the car back and it ran fine for about a week. Then, once again huge clouds of blue smoke started pouring out of the exhaust. We took the car back to the mechanic (yet again, 3rd time). The mechanic once again measured the crankcase pressure (it was positive), and confirmed that the breather box system was clear. He then did a “leak down” test, and found that there was 20-24% leak down in two of the cylinders. He said the engine needed to be either rebuilt or replaced in order to fix the problem (i.e. he suspected badly worn rings/valves). The next day, we tested the compression and found that 4 out of the 5 cylinders were getting a compression reading of 175 PSI. The 5th cylinder was reading 155 PSI. We also changed the oil to a slightly heavier grade (15/40), with no change in the smoke issue. We put a rubber surgical glove over the oil filler (with the car running), and determined that there was still positive crankcase pressure. We then phoned a couple of other mechanics and explained the problem. Both said that it was highly unlikely that we needed to replace the engine. One suggestion was that the turbo charger either had bad seals that allowed oil to leak into the exhaust, and/or we had a plugged turbo charger oil return line. Before we take the car to yet another mechanic and spend yet gobs more money, we were wondering what your opinion of the problem is.
Everything described indicates that the engine is worn out, and that the turbocharger is leaking oil into the turbine side.
The compression readings and leak down readings are not good signs of engine condition. And the blue smoke out of the exhaust could mean that oil is leaking into the exhaust side of the turbo, collecting in the catalytic converter, and when enough gets in the cat it lights off and the blue smoke appears.
Just with that info, I’d cut my loses.
Tester
Thanks for your response, but how do you account for the fact that we had absolutely NO problem with the car UNTIL the mechanic replaced the breather box? Also, according to other mechanics, the compression readings are well within normal.
I’ve owned two of these Volvos (a '98 and '00 V70XC wagons) and my advice is time to say goodbye to the Volvo. If you haven’t spent a boat load of money on the car already then you are lucky. My Volvos were constantly requiring multi thousand dollar repairs and eventually I just couldn’t afford to put more money into them.
Even if you fix this problem now, it will only be a few months before the next expensive repair will pop up.
It seems very likely the turbo is shot. If that is fixed it won’t help for long because the motor is “tired” based on the compression and leak down test results.
Worn rings would be blowing out the blue smoke all the time. They maybe worn but not to the degree to cause all the blue smoke you are getting. Also the Seafoam treatments seem to stop the smoking for awhile and then it returns. This indicates something in the all the emission hoses and crankcase ventilation systems is misrouted, clogged, or not attached.
The breather box is something I never had to mess with, and I suspect as you do that something in that job was done improperly and is the root of the problem.
A turbo with bad seals could be more likely to let oil by if too much pressure is pushing the oil past the worn seals.
These Volvos require mechanics that are very familiar with Volvo systems which are simply different and more complicated than most other cars. Is your mechanic a Volvo specialist? If not, then you need to take the car to someone else. Taking it back to the same guy isn’t getting you anywhere, more Seafoam is not solving anything.
Have your mechanic check the PCV system from one end to the other…Especially the vacuum fitting where it connects to the intake manifold. The other end connects to the breather box, but I think your mechanic was messing with the wrong end…You may have “low flow” in the PCV system and this would account for all your problems…
If that checks out, then the turbo is the next likely culprit. There are specialty shops that rebuild them for a fraction of the cost of replacing them…But the positive crankcase pressure is a red flag. Fix that first or move on…
Ok Couple of things.
I have a 2002 V70 and other then normal maintenance for a car over 15YO it runs FINE.I never would have bought it ( I got it second hand ) but at the time I was driving to a location for work on a regular basis and I have my F350 crew cab dully and a Harley. ( 400+ miles one way upstate New York.def need an option)
one question on the Smoke. do you smell it INSIDE the passenger compartment.? if so this is the result of a common issue with the 5 cylinder Volvo. A small leak develops in a gasket in the Volvo version of the ‘PVC’ process. it is one of these “it is a nuisance but NOT damaging to the Engine”. it does not even burn of any appreciable amount of oil. I only see it on hard accelerations.
Since your mechanic was in the general area…it sounds suspicious.
Again the key point here is you can smell the oil inside the passenger area after a hard acceleration. I found it was NOT a problem when the engine was cold.
Hope this helps.
GW
I don’t think the original poster is coming back after 10 years to read your comment.
… especially in view of the reality that the OP’s Volvo would now be 21 years old, and was probably junked long ago.
'Cause it was a smoking pile of Swedish meatballs… 
I always enjoy reading your posts.
Yeah, he tends to do that when new posters dig up really old threads…
It’s not much to worry about though.
Does make you wonder what happened though. I’d be fascinated to find out what the OP ended up doing. But then, I’m nosy.
Might not be them but I searched and came upon this note a few days ago. Might help some one else
Good point. Thank you for sharing it.