07 Cobalt drinking oil

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The oil could be getting sucked through the pcv hose that goes from the cam cover to the intake tubing.
 
I think GM just calls the pcv system on these an orifice, basically that's all it is.
 
Do you have oil collecting in the intake tubing that's on top of the throttle body?
 
That is the only place the oil would be disappearing to. Assuming that it is not leaking or burning oil. The intake tubing is very easy to take off. Just a few fasteners and work clamps.
 
If it's collecting oil then there might be a problem with the piston rings. I recall there is a member on this forum with a 2.4 ecotec Buick with a similar problem. Not sure what the outcome of that situation was.
 
For now, I would at least switch to a 10W-40 high mileage oil in the summer. Your consumption will drop if you were using 5W-30 or 10W-30 HM.
 
Oil can only leak two places, internal or external. External you can find easy enough especially at that rate but internal can be a few places.
Through the valve guides because of bad seals or worn guides, rings either sticking or worn and the PCV system. Valve guides and seals are easy enough to spot, you will get a puff of blue smoke when the engine is cold started, the cat has not lit off yet and you will clearly see the blue smoke.

PCV is easy too, just pull the hose, if its dry its not going there if oil is there you are getting blow by or a plugged breather or PCV/tube. Rings are another story, the compression and leak down test can be fine but the oil control rings could still be sticking as they have much less tension and thinner than compression rings. Worn rings can be found with a leak down test or even a vacuum gauge. Going to HM or thicker oil is not the answer for sticking rings, it only masks the issue.

With less than 100K I doubt the rings are worn out unless the engine had poor maintenance with the cheapest oil. First thing after checking the things you can see is to put a vacuum gauge on the engine, if it has 18-21 Hg then the rings are probably not worn to the point they would cause an issue.
A good ring cleaning might be in order. Its very easy to perform on a inline engine and usually has good results.
 
its summer. Excellent weather for trying pp 10w30.
Few with listed noack of 4.7.

Noack varies wildly in 10w30s and 10w40s etc.
Just look at pqia.

Pp or qsud 10w30 solved my expeditions drinking problem.

+1 on post above for air filter change and low cost fixes.
 
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Originally Posted By: stower17
I think GM just calls the pcv system on these an orifice, basically that's all it is.


^ This. I owned a 2007 for a few years. I don't know if the Ecotec 4cyl are still like this, but the vacuum side of the PCV system is internal w/ no serviceable parts. There is a small vacuum port/galley cast into the plastic intake manifold that mates up with a small hole cast into the cylinder head, that's ported into the cam cover area. I know if the intake manifold gasket isn't lined up right, this hole can get blocked, which is going to cause gunk in the cam cover and blowby into the breather.
 
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