[dandugi]

This is doing nothing for you. You have blocked off all chances of ventilating the crank case. If your lucky you will burn another valve. If your unlucky the crankcase will explode from the oil becoming volatile from lack of ventilation. There is no way that catch can will pull any oil. there is no vacuum pulling through the PCV system. As a matter of fact, you have no PCV system anymore.

You are wrong, it is vented. There is no crankcase pressure building up, it is completely open via the PCV valve (internal check valve was removed/drilled in phase 2, you can see through it). The catch can was installed in phase 1 between the PCV and the intake to measure the oil being sucked out of the PCV. I was measuring 1 quart every 600-700 miles, due to excess vacuum from the intake. In phase 2 the intake was separated from the OCC, eliminating the vacuum suction, and the oil loss. Now there is 0 oil loss, and vapor/gasses breathe out, the oil is not volatile. You can easily see and smell the vapors coming from the OCC breather, it is breathing just fine, and the intake valves are staying clean. The intake valves will never need to be walnut blasted like other GDIs. However, I see you have a turbo. I have seen online there is a different PCV delete procedure recommended for turbos.

 

[rio-t]

You are wrong, it is vented. There is no crankcase pressure building up, it is completely open via the PCV valve (internal check valve was removed/drilled in phase 2, you can see through it). The catch can was installed in phase 1 between the PCV and the intake to measure the oil being sucked out of the PCV. I was measuring 1 quart every 600-700 miles, due to excess vacuum from the intake. In phase 2 the intake was separated from the OCC, eliminating the vacuum suction, and the oil loss. Now there is 0 oil loss, and vapor/gasses breathe out, the oil is not volatile. You can easily see and smell the vapors coming from the OCC breather, it is breathing just fine, and the intake valves are staying clean. The intake valves will never need to be walnut blasted like other GDIs. However, I see you have a turbo. I have seen online there is a different PCV delete procedure recommended for turbos.

Breathers work just fine for boost also. Been around for a long time

 

[mgreen18.mg]

You have completely eliminated your PCV system. The engine is like a big house with two small windows an a lot of stale air. The best way to get that air out is to open both windows and put a fan in one window blowing the air out. What you have done is to close one window and taken the fan out of the other window hoping that that is enough to vent the air out. Oh yeah, and you started your BBQ pit in the living room. Sure some of that smoke and stale air will go out of that one open window but, in the mean time everybody in the house dies from asphyxiation. All combustion engines have blow by. That is when combustion gasses pass through the piston rings and go into the crank case. The PCV system was invented by engineers to remove these volatile gasses and put them back into the combustion chamber. If these gasses are not removed quickly, they can mix with your oil causing it to become volatile as well. Remember, oil is a petroleum just like the gas you put in your gas tank. When that small (used to be PCV valve) hole gets clogged up with sludge,(because the oil will start to coagulate and turn to sludge without proper ventilation) the crank case will build up with combustible gasses and explode. Probably blowing out your rear main seal while on a long trip in the middle of nowhere. You were fine putting the catch can. That's a good idea. But, when you blocked off the entire engine from fresh air flow through the crank case. That is where the problems start.

 

[rio-t]

You have completely eliminated your PCV system. The engine is like a big house with two small windows an a lot of stale air. The best way to get that air out is to open both windows and put a fan in one window blowing the air out. What you have done is to close one window and taken the fan out of the other window hoping that that is enough to vent the air out. Oh yeah, and you started your BBQ pit in the living room. Sure some of that smoke and stale air will go out of that one open window but, in the mean time everybody in the house dies from asphyxiation. All combustion engines have blow by. That is when combustion gasses pass through the piston rings and go into the crank case. The PCV system was invented by engineers to remove these volatile gasses and put them back into the combustion chamber. If these gasses are not removed quickly, they can mix with your oil causing it to become volatile as well. Remember, oil is a petroleum just like the gas you put in your gas tank. When that small (used to be PCV valve) hole gets clogged up with sludge,(because the oil will start to coagulate and turn to sludge without proper ventilation) the crank case will build up with combustible gasses and explode. Probably blowing out your rear main seal while on a long trip in the middle of nowhere. You were fine putting the catch can. That's a good idea. But, when you blocked off the entire engine from fresh air flow through the crank case. That is where the problems start.

You don't need an air channel without suction. But yes, two breathers are better than one. What you are missing is pressure differential. PCV can create a vaccum under the piston, that creates less drag on the power stroke, resulting in a slight increase in power. Vaccum over ambient is a minor % power difference. However, pressure in the crank case, is bad, you are correct. Breathers will never create vaccum, so there will be a slight loss in power (less then 5whp). But a pressurized environment will always push out to the lower pressure area (atmosphere).

Breathers are an issue for emissions tho, and that is a fact. So yes, you are violating emissions law and losing less then 5whp for a much cleaner engine. The reason the intake valves on gdi get dirty is because of oil vapor in the manifold. By removing this, you are saving the combustion chamber, injectors, and intake valves.

But yes, two breathers would be better. But deleting the pcv will not cause engine failure. Breathers have been around a long, long time. And work just fine on much larger, high boost engines with gapped pistons rings and much more blow by.

The reason the OEM has two is to prevent over vaccum, which, obviously isn't size correctly for all manufacturing tolerances and causes excessive suction (vaccum).

 

[bobdec]

I was watching this thread hoping to find a cause (see post # 9) . However it looks like the OP has found a solution, however we really are still guessing at the cause. Either too much vacuum, except there are thousands of functioning 2.4/2.0's out there not running through a quart of oil every 1K miles. Or somehow this engine is vaporizing an excessive amount of oil into the lower end that was ending up (via the old PVC system) hitting the intake. Wondering is this engine is headed for a catastrophic failure in the future due to the way the lower end is behaving. ? (just a dumb thought).

As far as atmospheric breathers, the old pre-PVC setups had a 1.22 to 1-3/8 inch diameter hole in each rocker cover depending on straight I6 or V8. In this case the OP is venting through a hole drilled in the PVC valve maybe 1/4 to 3/8 inch diameter, and what looks like a 2-3 feet of 3/8 to 1/2 inch hose to the catch can/vent filter. Although it is working. IMO just sticking a larger breather cap, available at speed shops, directly on the rocker cover would smooth out crankcase pressure fluctuations..

 

[ecanderson]

I'm with you, Bob. I've seen a lot of recent discussion here that only addresses the symptoms, which if you've got them, is an understandable target. But what I am NOT seeing is any information related to the underlying cause that really should be addressed. Why are certain of these engines such problems while the vast majority are not? As you say, there are tens upon tens of thousands out there that don't show excessive oil consumption.

There are several ways an engine can get into this ditch, but I have not yet seen an explanation by Hyundai/Kia or any independent analysis that explains what it is about certain of these engines that is the root cause. Impossible to believe that by now, no one has done a thorough inspection of a few of them to find out. Guessing that they all have something in common.

 

[rio-t]

It's an aluminum block with large water channels, high compression (11.3:1) or boost (10:1, but pressurized). Large scale manufacturer, cheap. I'm sure there are manufacturing tolerances. If a breather solves the issue of oil consumption then it isn't being burnt so no worries about the bottom end. I wouldn't worry about it. The other tube is like 3/8 open if you are worried about flow out the valve cover.

 

[trsdamocles]

What really is the oil consumption problem? I have 2 examples that go against each other. 2 cars in my family 1-2018 Sorento(2.4l), 2-2015 Sportage(2.4l). My wife's Sorento has oil changes every 4000 miles and up till now(40000miles) it did not consume much oil. It now consumes 1qt/1000miles. My Sportage had it's engine replaced at 60000 when it had engine knock and it never consumed more than half quart(maybe left in engine block) in 5500 mile oil changes. It now has 20000 miles on it and it still only missing half quart at 5500 mile oil change. What gives?

 

[josuet]

Damn! The more I read this thread the more I freak out. I just noticed my engine seems to have consumed a crazy amount of oil...not sure when it started but last I checked it was missing over two quarts. It had a minor leak from the head cover gasket which I have replaced now....I'll keep a close eye on my engine, but will flag this to the dealership so there is a record trail.

 

[josuet]

I'm coming up to speed with this issue. I didn't see the actual recall posted so here it goes.

Kia Recall: EXCESSIVE OIL CONSUMPTION NU/GAMMA/THETA ENGINES
https://static.nhtsa.gov/odi/tsbs/2021/MC-10189272-0001.pdf

 

[ecanderson]

I'm coming up to speed with this issue. I didn't see the actual recall posted so here it goes.

Kia Recall: EXCESSIVE OIL CONSUMPTION NU/GAMMA/THETA ENGINES
https://static.nhtsa.gov/odi/tsbs/2021/MC-10189272-0001.pdf

Big difference between a "recall" vs. a TSB. Probably best to use the correct terminology so as not to get people going in the wrong direction with this.

 

[josuet]

Big difference between a "recall" vs. a TSB. Probably best to use the correct terminology so as not to get people going in the wrong direction with this.

True. Thanks for pointing that out.

 

[97Tbird]

The common similarity seems to be the 2.0 turbo engines.

 

[bobdec]

I may be getting this thread off topic, as I do not have Kia Turbo Service manuals my questions may be off track.
A normally aspirated engine relies totally on manifold vacuum for PVC operation. A theoretical turbo engine loses manifold vacuum at higher RPM's and starts to pressurize as compressed air from to turbo hits the manifold. Therefore a new solution for PCV had to be implemented for turbo emissions requirements. Some turbo setups switch over the PCV vacuum duty to the turbo intake (vacuum) side of the turbo pump. Others may have different setups. How does the Sorento 2.0 handle PCV under boost. Could be the PCV vacuum source under boost be higher than non turbo intake PVC vacuum source.

Buy the way since turbo pumps/compressors don't like oil vapor entering the pump they built a catch can chamber to collect oil vapor that then got sucked back into the intake at non-turbo operation. Sounds horrible for any GDI setups, Kia must have a better solution !!!

 

[josuet]

So I went to the dealership for the oil consumption test yesterday. Results: 1 quart in about 1500 km (930 miles). The dealership tech says the issue is with worn-out pins causing the piston to wiggle as it goes up and down, scratching the cylinder surface. He pointed out the engine was burning oil (there was oil inside the exhaust pipe). I replaced the sparks recently (when replacing the valve cover gasket), and they were dry as popcorn. In any case, I'll keep adding oil I guess....

 

[chuckwalla]

The dealer won't do anything about it?

 

[josuet]

The dealer won't do anything about it?

Nope. Unless the engine siezes or develop a knocking sound, there is nothing they can do.

 

[ecanderson]

Nope. Unless the engine siezes or develop a knocking sound, there is nothing they can do.

They DO understand how easy the former would be to 'arrange', don't they? It's not like they're going to tear down the motor at the dealership.

 

[josuet]

They DO understand how easy the former would be to 'arrange', don't they? It's not like they're going to tear down the motor at the dealership.

I discretely asked the services mgr if there was anything they could do to speed up the engine replacement. He replied that Kia HQ is quite strict about engine replacements and they ask for lots of graphical/chemical evidence before approving. Even told me that a few requests have been rejected in the past because the engines did not exhibit all documented symptoms.

 

[steelwindmachine]

any updates to the OP's oil consumption or anyone else?

Mine is a USA-market 2014 Sorento with 3.3 V6, ~90k and it's starting to eat through oil. Replaced original, seemingly fine PCV with new - didn't see any evidence of oil pass-through. Been running Penzoil Platinum 5w30 at 7000 mile OCI on recommendation from Blackstone after some oil analysis had been performed.