Hi
My V70 2004 started to have noise under the hood, that stops with pulling out oil dipstick or taking off oil cap. At same time appreciable vacum can be felt at dipstick and oil cap oppenings. My mechanic freind saidthat oilseparator cluging causes this problem. I found similar explanations on some forums. However I do not understend how oil separator can cause excessive vacume in crankcase. Is there any valve that conects oil separator with intake manifold negative pressure. Is it possible that not separator but such valve causese problem with nauise from excess vacum in crankcase.When I had problems with PCV system on my GLT850 I had smoke coming from dipstick and oil cap openning and there was positive pressure and not vaccum. Does V70 2004 model has fire trap or substitue and may it be clugged?

Thank you for sharing your experiance and expertise

 

My V70 2004 started to have noise under the hood, that stops with pulling out oil dipstick or taking off oil cap. At same time appreciable vacum can be felt at dipstick and oil cap oppenings. My mechanic freind saidthat oilseparator cluging causes this problem. I found similar explanations on some forums. However I do not understend how oil separator can cause excessive vacume in crankcase. Is there any valve that conects oil separator with intake manifold negative pressure. Is it possible that not separator but such valve causese problem with nauise from excess vacum in crankcase.When I had problems with PCV system on my GLT850 I had smoke coming from dipstick and oil cap openning and there was positive pressure and not vaccum. Does V70 2004 model has fire trap or substitue and may it be clugged?

Thank you for sharing your experiance and expertise[/quote]