# Very high oil consumption



## marco0 (Aug 20, 2020)

Hi,

I recently did a full oil change and filter replacement and after 400 miles on cold i noticed the oil level was on minimum.
Went to the mechanic who did the oil change and he said the engine head is probably broken and that's why the car is eating all the oil.

I went to a Chevy service mechanic and he says the oil used was wrong, he suggested a specific brand which later i discovered only makes 20W-50 oil. Honestly i can't trust this man because suggesting a thicker oil is low-key admitting that the car has a problem and will be thrown away soon. Also the car manual says to not use 20W oils...

Went to a friend mechanic and he says there is obviously something wrong in the engine, could be the piston rings or something else but he has to tear it down and check what's going on.

On my side i'm just seeing these oil consumptions but no leaks, no smoke or anything. Do you have any suggestion?

EDIT: i also want to mention that i recently replaced the engine cover (code 55564395) on my own, i just want to be sure i didn't messed up everything because the PCV valve has a problem or it isn't thight enough, even if i don't see oil leakage from there.


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## Thebigzeus (Dec 2, 2018)

What engine do you have?


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## snowwy66 (Nov 5, 2017)

I'm curious as to the specific brand?

Is this your first notice of consumption?

Did you switch brands by chance?

Have someone start your car after it sat a few hours. You watch the exhaust and see if any smoke comes out on startup. That could be a sign of oil dripping past the valves.

After warmup. Drive and watch the rear view mirror. Full throttle while driving and if you see smoke. That's oil being pulled in through the valves.

Next. Motor at somewhat high rpms . While driving. Let off on throttle. Smoke indicates oil being sucked past the piston rings.

No idea on how to test the turbo. But that could be a likely cause also. Or defective pcv.

You could also pull the dipstick out and engine running. Look for blowby smoke coming out of the tube. Might get a better picture with the pcv hose but I have no idea what the pcv setup is on our cars. Another way would be to take the oil cap off. But I don't know if there's a plate under the hole to keep oil from splashing out.

Blowby smoke is a sign of worn piston rings.
Confirmed with a compression check.


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## marco0 (Aug 20, 2020)

Forgot to mention it's a 1.8 LPG.
The oil brand suggested by the mechanic is called HPX. I don't know if i switched brand because latest oil change was made by another mechanic.
Now i filled it with some GM original oil which is a 10W/50. I don't understand why they say 5W/20 on the documentation and then sell 10W...
I will try to check better if smoke comes out from the exhaust but last mechanic said if the fault is on the piston rings you see smoke only on high speed and i will probably never notice on the road.
Do you think there is a way for a mechanic to test the engine and be sure it's faulty before tearing it down?


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## Mr_Pat (Mar 7, 2021)

compression test will tell you if theres a problem internally .


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## snowwy66 (Nov 5, 2017)

Oil gets past the rings when the throttle is closed. Putting the engine in vacuum mode. Sucking oil in to the compression stroke and out the exhaust.

When the throttle is open. Your in pressure mode. Oil would push back in to the pan.


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## marco0 (Aug 20, 2020)

The mechanic removed the sparking plugs and showed me one of them was burnt. Then showed me the same cylinder was wet inside, while the other were dry. So there is oil reaching the top of the piston. That probably means the oil is not pushed down correctly and ends up in the combustion chamber. That might be an ovalized cylinder or a damaged ring. I'm no mechanic so tell me if this reasoning might be correct.


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