New pvc oil separator but still oil out crankhouse breather hose hose

[PoloPacific]

Hi everyone,

I have a peculiar problem with my Polo 9N 1.2L
I had a oil leak from the old pvc oil separator so I replaced it with a new one, Oil leak is fixed but now it seems to be a high oil pressure in the engine. No fault lights and engine runs well but the crankhouse oil breather hose gets blown off and it splatters oil through that tiny hole and all over the engine bay.If I open the dipstick while holding the hose in place then oil comes out of the dipstick tube.
To drive the car I've been forced to mount a catch can (0.5L bottle) which fills up in under 20 min.

Can it be the little pvc valve located on the airfilter housing that is clogged or stuck? The breather hose goes from the crankhouse and to this valve.
One question though..should the breather hose spew out so much oil?

And should there be a strong vaccum from the pvc oil separator when I take of the hose that goes into it when engine is running?
Also..when I disconnect the electrical connector nothing happens.. is this normal?

I appreciate any answers!

[johntheo2]

Did you renew the diaphragm or is this what you are talking about? which is very important as it allows the crankcase to breathe and keeps the pressure right down, if its blocked/stuck then the crankcase pressure will build up very rapidly, the other one is a non return valve that allows a constant flow of fresh air into the crankcase, you can check this yourself.
What electrical connector are you referring to?.
These photos are from a family 2005 Polo 9N. (taken at night)

Good info here re the crankcase ventillation.
https://procarmanuals.com/vag-ssp-260-1 ... l-engines/

There is also a (over) pressure limiting valve (page 17 onwards) but don't know how to access this.

[PoloPacific]

Hi, thank you for this info.
I have not changed the diaphragm as I did not know this.
I will also check the return valve you write about.

I have replaced the oil separator which is located on the backside of the engine, and I will soon replace the little valve on the air housing. Please see pictures.

Some say the oil separator can freeze in cold temps and right not its freezing cold here in Norway, but I find it hard to believe, that means every polo in the country would start acting up and give problems..