[sm=dontgetit.gif]Hi to all

I have a Nissan Serena 2.0i Petrol, Which has just had a recon short block. it run for about a week, but then started lumpy, on investigation i found the breather pipe which connects to the front of the rocker cover was sucking heavy. when i took it off the engine started to run smoother. I was told the breather pipe was blocked, but i have checked the pipe and it was clear. Is there anyone who can suggest anything else.

 

is that line really needed?