Filler Cap Sludge and Blowby.

[cartandpeg]

Hi,
VW Golf Mk4 2.0 ltr with 220000 klms on the clock.

I have cleaned the oil filler cap many times removing sludge from it. After I clean it and replace go for a short drive I have water droplets on it.

Yesterday I took the rubber hose which comes out of the filler cap hole to the intake pipe off and it was full of this brown sludge.

Cleaned all that out and the wife says the car feels much smoother to drive, she does a 25klm drive to work, lets the car sit all day then 25klm drive home, all highway driving. Still very cold here weather wise.

I am assuming that this is a condensation build up as there is no indication of water in the oil. There does not seem to be any coolant lose. This is not worrying me to much as doing some research, this seems to be the norm to a degree.

Out of curiosity I took the oil filler cap off when the engine was running and there seems to be a fair amount of blow-by coming out. Rev the engine and it is not as bad. I am comparing this with my V6 Holden Commodore, none comes out of that.

I know the engine has a few klms on it and I do not know any past history of the car.

Any thoughts please.

Thank you.

[Umai Naa!!]

It's pretty normal to see some sludge build-up there.

That 'blow-by' is normal crankcase pressure.

Maybe run an oil flushing agent through it before you next change the engine oil.

[cartandpeg]

Thank you Umai Naa

[Transporter]

Did you change the engine oil yet? The previous owner may have done too many short trips and there could be a lot of water content in the crankcase. As suggested use the engine flush and change oil and filter.

[cartandpeg]

Transporter, yes I changed oil and filter on the weekend. This is the second change since purchasing car 3mths ago.

I will do engine flush next time service is due as I do oil and filter every 5000 klms.

Cheers.

[bloödstorm]

Air coming out of the oil filler is symptomatic of a bad PCV system. It's relatively cheap and easy to replace the PCV valve itself and the plastic 'puck' valve on the intake pipe (I'm assuming the 2.0 PCV system is much like that on my 1.8T).