My daughter drives a non turbo S70, which has been very carefully well looked after (by me) over the years, i.e. synthetic oil, regular oil changes, fuel filter change, good plugs etc. The car is about to turn 300,000 km, runs great and has no oil leaks. I changed the oil in it the other day and checked to see if the pcv system was functioning properly by idling the engine with the oil filler cap off and holding cellophane plastic over the opening....no suction detected. Does this mean that the pcv system is plugged, and does anyone have advice as to how to proceed next? Thanks very much for your interest!
Tony

A little harder to do when your engine is wireless throttle; you should have revved it up to about 2K and then suddenly close the throttle for best vacuum test OR find a vacuum gauge and hook it to the vacuum tree.

Your dipstick O rings could be worn and letting air in that way, negating a tight engine seal.

Befor you replace the oil separator box and its lines, make sure the small vacuum line to the front of the throttle body (old PCV valve) is clear.

Klaus
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Proud owner of a 220S. If I had more room, I would have more Volvos.

I really appreciate the excellent advice guys. It's still pretty mild outside, so I'd better get at it. I will do the cellophane thing again, but this time make sure the oil dipstick pipe is fully sealed and the engine gets revved up as you suggest.
If I still get no vacuum, I'll check that hose with the plastic nipple I keep reading about on various posts. Failing that it'll mean the breather box I guess.
Tony

Would you know if the 99 S70 non turbo still has the flame trap like the 98's?
Thanks

I believe it does and it needs to be cleaned out. There is no PCT nipple on an NA engine, Just a PCV valve.

Don't sweat the little things too much. Constant use of synthetic engine oil will keep the breather box fairly clean. Just tell your daughter that the engine oil must be brought up to temp at least once every 2 week or so, just to burn off the contaminates.

Happy turkey day,

Klaus
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Proud owner of a 220S. If I had more room, I would have more Volvos.

Hey Klaus,
Thanks very much for your reply. As you suggested, I did rev the engine when testing for suction at the oil filler opening and found there was some. I've been running synthetic in this car for years, along with regular oil changes. There's no oil leaks and it doesn't see a lot of slow city driving either, so I'm pretty relaxed about it now. Just want to make sure the engine will go well beyond the 300,000 km
Thanks again,
Tony

your 'no suction' condition is probably an early sign, but I wouldn't throw the panic switch just yet.

Early winter can be a bad time for these PCV systems as I found out last year. Something about the colder temperatures really exacerbates any problems in there. If you live somewhere that gets cold in the winter it's best to get any PCV probs out of the way before the cold comes. Unless you like dealing with chasing oil leaks and tearing the intake manifold off when it's freezing cold outside. I went through this last winter... at around the same mileage you have on your car (~190k miles == 305k km) though I had just purchased my car and have no idea how it was treated before I got it - you have a good history of synthetic oil which might help you last a little longer.
http://www.brickboard.com/AWD/volvo/1356259/850/weird_oil_leak.html


That said, have a look for 'smoke' coming out of the oil dipstick. In my mind, that would be a better indicator that you've got to do the work right away.

You want to get this done before it starts pushing oil out the engine seals anc causing real problems, but many of them seem to go a fair number of miles with early signs before starting to cause problems like that.

Klaus has mentioned a few times on here that AutoRx might be able to help this situation and buy you some more time. Eventually I think the PCV systems will need to be replaced on all these cars, synthetic oil or not.

It's also a great opportunity to change all the vacuum lines, clean the throttle body, and replace the seals on the oil dipstick and tube, while you've got everything apart. Not to mention the easy access to the starter and back of the alternator, AC compressor, trans oil lines rad hoses. Any maintenance on these items can be bundled into the job as well. Although you should be warned you're looking at a pretty long day for just the PCV system.