S40 1.8 2006 - PCV valve/hose replaced. Still issues
 

Hi all, my car recently failed MOT on emissions test and thought it might be the PCV valve, so went through the aweful job of replacing it and the hose.

The reason I thought it was the valve was because the engine is blowing out the oil filler cap - apparently a classic sign of the PCV.

Valve and hose replaced but still same problem, still burning oil. Is there anything else I could check, as I believe its still going to fail the emissions test.

Another thing to mention would be that, there is smoke coming out the exhaust gasket at the back of the engine when up to temperature. I bought a new cat and mounting kit, but don't want to put it on if the oil will ruin the new cat.

As far as I remember,the 1.8 engine is pron to worn piston rings...

I'm experiencing the exact same issues and tried the exact same. Have you managed to resolve it?

Smoke out of joint at gasket will definatly throw off emissions as will burning oil,try gasket on it and see and perhaps something like Lucas stop leak and maybe switch to grade heavier oil if it’s high mileage too?might scrape you by for another year,I’d successfully on e46 bmw with me oil filter and Lucas passed emissions so worth punt if can do it yourself for few quid and get another year or two out of it