So recently, I've had to do a fuel injector replacements (3 times actually) and each time I use new intake manifold gaskets. Every time I open it up, I see large amounts of fresh oil and baked on oil ALL over the gaskets - to the point where the gaskets are falling apart when removed. I could understand if it was a long time and had just built up, but this is happening from a day or 2's worth of driving.
I've dug all over the web and maxima.org, and it seems like most people that have had similar issues just replace the PCV valve and problem solved. I replaced my PCV a few weeks ago, and the same problem keeps happening - and yes, the valve still functions as it should (1 way air flow) This will be my 3rd set of gaskets and I'd really like to make it the last!!

I have also heard of people saying that you can install an "oil catcher" in line from the rear valve cover before the PCV - does anyone know where I can buy these or how much they cost ? I'm assuming that it's an aftermarket "universal" style part, though I'm not sure of it's proper nae so I know what to ask/search for. If it makes my manifold nice and dry, I'll gladly give anything a shot.

 

Oil catch can should be great. But, sounds like you've got some issues with rings and/or valve seals. If you get a can, just make sure the openings are large enough (5/8"?) .....I can't recall. I just know I bought one off eBay one time and the holes were tiny, not large enough to be useful on the size line coming off the PCV.

An oil catch can will give good information about how bad your blowby issue is. May not be bad enough to be of concern. Seafoam treatment should clean out the intake quite well.

 

yeah, I'm leaning towards just using the catch can. I guess what is stumping me is, WHY is so much oil blow-by happening in the first place ? oil levels on the dipstick are a tiny bit higher than likely recommended, could that be an issue ? I can tell where all the oil is coming in because I cleaned out the plenum/manifold so it's really easy to see the path of the oil entering the intake manifold - ALL of it is concentrated in the PCV "channel" in the middle of the plenum.

 

I just hope it's not piston ring issues, since I can't really do that level of engine work ..........plus I've already put way too much time and money into fixing this ol' girl up :/

 

These engines tend to have some blowby, especially as they get higher mileage. Its a ring issue most often. Common and not a huge problem if monitored (ie: catch can and checking oil levels).
Most people don't know this, but Nissan even puts a wire brush looking thing inside the rubber tubes off the front and rear valve covers. This serves to slow blowby and catch potential debri from getting sucked into the intake or PCV valve. Either way, you'll be fine with the catch can.

 

yup i saw the brush in the hose

 

interesting, i found this brush in bank 1 valve cover while doing the valve cover gaskets a few weeks ago and i just tossed it out thinking someone might have left it in there and forgot about it, is this going to be an issue?

 

Couldn't say. Oil passing by the brush gets caught and some, definately not all, will collect and then drain back into the valve cover. Think of it as an inline air/oil seperator. Without it you will pull more oil in through the PCV or intake. How much more would be an uneducated guess. How effective is the brush to begin with? Another uneducated guess.

 

Well, i wouldnt notice the difference since my car is still missing more parts before i can actually start the engine.