I've had this issue for a couple years, but just recently have gotten to the point of it not being able to be overcome...

Background...

Engine was sludged to the point of needing new pickup screen when I got it 70k miles ago. Cleaned out- in business...ran great...

Couple years ago it started barfing oil into the PCV and therefore into the upper intake plenum- smog the neighborhood and ping all over the place... I added a "catch can" and would empty it ever say 6 months or so...

Not sure what changed recently, but now it will fill up a quart jar in maybe a couple hundred miles...I've tried to put it back to stock but no go...

Next step for me was to inspect the crud at the top of the engine to see if I can clean it off that way...any other suggestions?!!? Just ran compression and all seemed happy in the world- leakdown is in my future, but I don't have the tools so I'm going to have to find someone to help me...

Thanks in advance...any help at all is very very very wonderful...

Dave
1993 E350, 5.8 bone stock 170k miles

 

When you inspect the top of the engine, also check the oil drain back holes in the heads. These can get restricted by crud deposits to the point that the oil doesn't drain back fast enough, resulting in it getting sucked into the PCV system instead.
Thicker oil exacerbates this problem.

It's a long shot, but also check that the dipstick is correct for the engine. An incorrect one could have the oil marks too high, causing chronic overfilling.

 

I'm digging into this early tomorrow...I'll post my results and maybe take some pics of what I find. I KNOW that the baffle under the pcv grommet was filled with crud...totally caked, so I'm assuming I'll need to clear those holes...any recommendations on what to use to clean them out?

 

It was really ugly in the valve covers and the return was plugged it n the passenger side...

I'm taking the intake off to clean it out and then the pan...

Thanks for the insight...

 

Good to hear that you found the clogging. If you don't mind paying a few bucks, you could bring in the intake etc. to an engine or transmission rebuilder and have them put it through their jet washer. It saves a lot of elbow grease and the parts come out pretty nice.