I'm checking out possible excessive crankcase pressure, and I removed and cleaned out the EGR over the weekend.

The breather pipe from the rocker cover was fairly clean with just some oily residue but no build up or deposits.

I have a 1.9 TDI bxe and the rocker cover has a sealed pcv.

I have watched a few greek videos where the pcv is split open to get inside, and there is a replaceable diaphragm and spring. It appears the cap is then glued back on using a suitable silicone adhesive.

This one for example....

 

Has anyone here done this successfully? Or can anyone suggest how I might check for a damaged diaphragm before taking things apart?

And does anyone know why I can't find any uk videos of the same thing??

Thanks for any suggestions.

 

If there is gas outflow from the PCV then it should be operating normally, the inlet pipework will have lower pressure so any flow can only go in one direction.

 

I'd only suspect a problem if there is no outflow from the PCV but obviously some from the oil filler cap and dipstick.

 

Why do you think you have excessive crankcase pressure?

Thanks MicMac, I don't know if I have excessive crankcase pressure but the rocker gasket appeared to be leaking and maybe also the rear main seal. I cleaned them off so going to see what develops. I have to confess to missing an oil service too - so I'm trying to make up for it by giving the car some TLC now.

The EGR was pretty oily and crusty too - and I wondered where the stuff was coming from. If the PCV diaphragm was split and caked in goo like in those videos, I assume it would be a bad idea to leave it like that if it can put lots of deposits into the EGR and turbo. But I just don't understand why it would be sealed so it can't be swapped or checked like most other PCV valves. A new diaphragm is £15, but a new rocker cover is a whole lot more.