Ive just noticed when i pull out my dipstick with the engine running it doesnt run rough atall it just keeps ticking over nicely. When i pull my oil cap off there seems to be some pressure and i can see a bit of smoke bellowing out. Now a while ago i removed the pipe between the pcv and the inlet manifold and blocked it off. Would this explain why my car doesnt run rough when i pull the dipstick? is there a vac leak elsewhere? could the rear vale be knackered? thanks