Originally Posted by
BenFenner Will, it's not an oil separator (okay well it might be but it's not part of the normal PCV system). It's part of a different system which I think is responsible for some types of emissions. I've never had it on my car so I'm not familiar with it. Miko has a good thread about it, and why it's not really beneficial to remove it. For sure, it shouldn't have that breather filter there though. Good catch.
I can't even remember what the system is called to search for it. IAVC or something... It was on '91 and '92 engines I think. Maybe on '93 as well?
Oh right, it's on my nx. The black box does do some oil separating I believe... Isn't there a tube that runs from the crank case down near the exhaust manifold on the block to the bottom of the black box? IIRC it is baffled or whatever inside which separates oil and allows the crank case to vent up to the pipe that runs behind the distributor and Ts into the valvecover vent then into the intake via the hose you mentioned earlier.
Originally Posted by
92SentraSE-R
It goes to the stock air box and when you remove the air box you remove that also.. When I bought it, it was already out with the knn filter on it
You should run a hose from where the breather filter is to the intake. When that hose broke on my NX it caused a really bad idle.