what is this leak?
 

hello all, did an oil change today, and when I removed the plastic engine cover (2006 Ion 2.2 Ecotec) found oil and remnants thereof right here. Any thoughts? thanks Attachment 1401

That looks like a PCV valve, but it's not a valve.
It looks like it is a pressure release port and may in fact be the exit of the PCV system that is designed into the head.

Anyway, the other end is feeding into the air inlet ducting where it attaches to the throttle body, with the standard design of routing PCV vapors back through the throttle body to be burned.

Either your oil level is way too high or there is excessive pressure in the head forcing oil out into the hose---or that hose could be clogged, leaving the oil and oil vapors nowhere to go except into the air, where they cool and condense back onto the valve cover. The top of the valve cover has no condensed oil on it because the plastic cover shields it.

Since you change your own oil, I'll assume you know how many quarts to put in.

That leaves excessive pressure and hose blockage.

Pull the cover off from over the throttle body entrance.

If the area is soaked with oil (more than a vapor coating), the hose is not (completely) blocked and you are pushing oil out that port.

If the area is bone dry, the hose is probably completely clogged.
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How does the engine run and idle? Do you have misfire codes or a rough idle?

MIGHT be a compression ring or head gasket issue, with a compression leak into the crankcase that is overpressurizing the system and blowing oil out through that orifice.
Might just be the PCV system on the car is blocked up (I think it is internal to the head ?)
Might be a blocked oil drain passage in the head that is causing too much oil to remain up there, and the extra flows out the fitting.

Bones --- come answer this correctly please. Or Andy. Or whomever.

thanks for the response, engine runs and idles fine, no codes. I'll start checking into it, and yes I know how many quarts go in :), and I always check the level on the dipstick after the change.

Even though you are running fine, you may wish to do a compression test across all four cylinders. If you find a low cylinder, it may be 15-20% lower than the rest but not low enough to mess up normal operation. Directions are on the net. Don't forget to pull the fuel injector fuse. This is a longshot.

Prob just the hose. Start there.

My L200 has the hose connected to the hose coming from the filter. So it sees filtered air, I think these engines have some kind of metered orifice not a pcv valve. I will look in my fsm about the crankcase ventilation system and get back to you.

They describe the crankcase ventilation system as having a " properly mounted PCV vent housing". I will look again tomorrow night when i get home. I have an engine on the stand that is going in my L200/5 speed car.

I figured the draft of the fresh air going by would aid in pulling the vapors into the throttle body. I'm pretty sure these ecotecs have some funky pcv setup