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Engine Catch can

You're overreacting plain and simple and seriously need to calm down.

You're repeating yourself time and again. What you're referring to is simply semantics. You have no factual long term evidence to refer to with the Hyundai i30N and VN engine.

Every dealership from every manufacturer offers these services. Hyundai is not the only manufacturer by far.

Besides you're beginning to rant and not making much sense. This is not debating. You've repeated yourself with the same information, so many times in different threads, it beginning to sound like a recording.

Observation of your personal comments have shown, you're afraid of what you own and are attempting to convince others of that same fear. You bought the car, no one twisted your arm. You have to deal with your own servicing, problems and fears.

There is no debate here, just you're personal speculation. You've written 5 successiver posts with no pertinent information, specifically regarding the 2.0 Theta II engine. Why, because you haven't any.

It might be best to quit assuming other owners are not aware or informed, that you're more of an authority then they are and the only one who can read or understand.

Members on this forum are enthusiasts. They chose the N because it suits their niche and desires. It's not an imposition to them but a positive aspect in their lives. Try to leave it that way, without all the personal insistence that it's not. You have your way of thinking and others theirs. It doesn't mean you right but your not going to convince others, by beating a dead horse to death.

You've attempted to convince someone by making 5 successive posts haven't you? It's actually become quite repetitive with regards to this thread to several others. Why not take a breather and calm down?

I do the maintenance regardless of your comments, insistence or otherwise. So do others. I'm not afraid of what I purchased and have no qualms about the engines reliability. I conduct preventative maintenance on everything I own, as I invested my money into it and wish to take care of it. I don't wait and ignore it, until have to spend a $700 to have the head dismantled and the valves cleaned.

So now, you're action is to overreact and convince others it's necessary to do the same. I don't need to over react, neither does anyone else. Just keep a good maintenance schedule for the car.

Keep this in mind, I have nothing to prove to you, for any reason. You don't know me or how I maintain my cars, etc.

I don't agree with your reasoning because, you have very few miles on the VN respectively and are speculating about something you're not fully aware of.. Miles and maintenance will tell. Until then, it's all speculation on your part. Enough said, as far as I'm concerned.
 
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You're overreacting plain and simple.

That's your opinion which I respect like everyone else's. But as a mechanical engineer, you gotta hit me with facts or evidence to back up your claims lol. Can't call my results negligible without sufficient and reasonable logic to back it up plain and simple. If you don't wish to put a can on your vehicle don't. But I simply provided findings from my own testing on my own vehicle. Others have had similar results. Others have had different results. I don't work for anyone who makes catch cans nor am I trying to promote any agenda. Simply stating my findings. But you can't comment on my findings without facts to back it up lol. Plain...and simple. I see you don't have a rebuttal for my responses so I'll leave it at that. I'll be looking forward to you posting your own findings with your own logic to add knowledge to the Veloster N community in the future. :)
 
Not as badly as you think. You are talking about two different engine in the Hyundai and VW. the VW bing the far worst of the two. The VW engine has considerable blowby which causes the coking problem far worse than the Hyundai 2.0T Theta II.

I can clearly see you're particular overreaction based upon the VW engine. I believe others have also. Not all GDI's are alike and so far, the Hyundai 2.0T Theta II isn't a problem. With a fuel dilution of less than 0.5% the amount of fuel/oil/water vapor is not a significant amount, nor is it near the fuel/oil dilation levels that most VW engine have.

Cleaning with the BG system at 15K intervals is not expensive and just good insurance for the long run.

The supporting evidence is out there from other VN owners. Some have actually removed their CC systems. The amount they're collecting is even less than what you've collected. Common sense and understanding fuel/oil dilution levels is necessary and not jumping to on substantiated claims. Frankly, your claims do not favor the use of a CCV/PVC CC system. Maybe if you were having twice or three times the amounts per oil change but not at the insignificant amounts you've demonstrated. Also combined with over 3.5 percent fuel/oil dilution which you clearly aren't getting. Even at a 3000 miles interval.

You first have to understand it's not the oil that cokes the valves. It's the combination of fuel/oil/water vapor. You're just not producing enough fuel/oil/water dilution or vapor. The oil you're catching is moved back thru the PVC to be re-burnt. The engine was designed to reburn this amount of fuel/oil/water/vapor. The majority of what you collecting is comparatively small and the valve cover filtration utilized on the 2.0T Theta II is working quite well.

To be frank, you can afford to be changing the oil every 5K miles based on the lab results. I also believe this is what the lab suggested as well in the comments. What you're doing is going to the extreme end, based upon your past experience.

The use of a catch can for either side is not mandatory with this engine, unless you're utilizing the car for a lot of short, slow speed trips and in stop and go traffic. You're attempting to convince other owners it's the best thing to do and clearly it's not, based upon your own results.

I've had similar results in oil lab testing in comparison and it just doesn't warrant the mandatory use of a CCV or PCV catch can. So it then comes down to, individual choice to utilize one or not.

Now, no one has equaled or surpassed 60K-80K miles as of yet, so it remains to be seen how much actual coking will occur. If owners are doing their the diligence; changing the oil at no more than 5K intervals, utilizing high quality spec synthetic oils and have regular valve cleanings, I see no foreseeable issues, as you experienced with the older VW engine.

You're speculating to similar coking issues, without a basis of factual information regarding the Hyundai engine, clearly. Most owners are clearly aware of how a GDI and multiport fuel injections engines work, so we can for go with the continuous rehash of researchable information.

You have no data to support your belief regards older engines verses, turbocharged engines. It's merely personal speculation. I understand you had a bad experience with the VW engine but this is your impression solely and past as well. It doesn't mean you'll experience it with the Hyundai engine. As the miles wear on from both the VN and i30N, everyone will be made aware of any such issues, if they become prevalent.

Personally based upon first hand information, you're testing as well. I certainly don't believe either the CCV/PVC catch cans are to be considered mandatory or will provide any additional preventative benefit if normal maintenance is completely by the owner.

Forgot to address the very last comment in full. Again never said can was mandatory it's just another step. Strange for you to say that a can will not provide any additional preventative benefit if normal maintenance is completed by the owner....but you're taking additional preventative steps to make sure you don't have any carbon buildup on your valves... Chemical cleaning of valves is NOT normal maintenance for our vehicles as per Hyundai specs. There is no literature or instruction that I know of that states for owners to manually chemically clean there valves every 10k miles or have a professional do it every 10k miles. Do they even mention carbon buildup in the manual? I would love for anyone to point this out to me...Maybe it's in the service manual? I have not seen it there either. So basically you are contradicting yourself here. You are discrediting one method to prevent carbon buildup while also performing another method to prevent carbon buildup while claiming you need to take no additional steps to prevent carbon buildup...very confusing lol
 
I'm not contradicting anything I've said. You're simply taking issue with what I've said on your own terms. You're presuming far to much and know very little about what your addressing with me personally.

I'm not going to attempt to justify to you my personal thinking, as you'll continue to take issue and find fault where there is none. This is your present methodology. There is no argument here however, you wish to construct one.

I'll say this in closing. You have issues with the GDI in general, I don't. You are fearful of the engine obviously! Why, because of your personal bad experience. I don't agree with your analogy as you base it on one particular instance in the past. You don't have the technical data to prove what you are speculating about this particular engine.

I don't care what you do with your VN but you're not going to convince me a CC is necessary for this engine.
 
I'm not contradicting anything I've said. You're simply taking issue with what I've said on your own terms. You're presuming far to much and know very little about what your addressing with me personally.

I'm not going to attempt to justify to you my personal thinking, as you'll continue to take issue and find fault where there is none. This is your present methodology. There is no argument here however, you wish to construct one.

I'll say this in closing. You have issues with the GDI in general, I don't. You are fearful of the engine obviously! Why, because of your personal bad experience. I don't agree with your analogy as you base it on one particular instance in the past. You don't have the technical data to prove what you are speculating about this particular engine.

I don't care what you do with your VN but you're not going to convince me a CC is necessary for this engine.

lmao idk what you're talking about dude. Again nobody is trying to convince you of anything. You've had multiple back and forths with many members of both forums both overseas and American. A lot of them where the interactions are testy. Clearly the issue here is you as you are the constant denominator. You try and use antagonizing words like im "fearful" or "I know very little" lmao. I've never said that you know very little or you are scared lol. I simply respond to your statements with facts but you have no rebuttal. Have a seat sir. You commented on my findings and called them negligible. I did not comment on any original content you have posted claiming that the results are this or that. You start the convo, have no evidence to back up your claims, and then say I know very little. Okay man lol. I just explained exactly how you contradicted yourself and again you have no response. If we're not gonna have an intelligent convo here there is no need to have one. If your not gonna respond with facts but only statements about me personally it just proves my point that you don't have any evidence or logic to back up your claims. Your just saying things... contradicting things... I have literally been posting items for months about my own personal findings. And I believe in the other forum that you are apart of I have literally posted photo evidence of carbon build-up with these Theta Engines. Like I've said multiple times I've actually worked for some of these major car corporations such as Ford and Toyota. I work with manufacturing engineering for a living. So unlike other members, you can't just claim things towards me with little to no logic or reasoning behind your statements. If you don't have a legitimate argument to make then don't respond to my content. Simple as that bud.
 
I'm not contradicting anything I've said. You're simply taking issue with what I've said on your own terms. You're presuming far to much and know very little about what your addressing with me personally.

I'm not going to attempt to justify to you my personal thinking, as you'll continue to take issue and find fault where there is none. This is your present methodology. There is no argument here however, you wish to construct one.

I'll say this in closing. You have issues with the GDI in general, I don't. You are fearful of the engine obviously! Why, because of your personal bad experience. I don't agree with your analogy as you base it on one particular instance in the past. You don't have the technical data to prove what you are speculating about this particular engine.

I don't care what you do with your VN but you're not going to convince me a CC is necessary for this engine.

Obviously I'm not fearful of the engine because I purchased another GDI Turbo setup. I have never uttered the words that catch cans are necessary for this engine. You are putting words in my mouth for reasons that are unknown lmao. I'm simply stating that carbon buildup will be an issue and it needs to be addressed. And you are addressing it on your own vehicle with chemical carbon cleaning but for some reasons you dislike catch cans? I don't get it, dude, lmao. You are saying that the air oil combo that is flowing over these valves doesn't matter but you plan to clean your valves...totally contradicting yourself my man. But engineering facts are facts. Ignorance is truly bliss but most American car owners don't deal with major maintenance issues with their vehicles because they sell their vehicles in 2 to 3 years. Check the statistics. Half the luxury cars on the road in America are leased...check the statistics. So most people never deal with or ever see carbon buildup on their GDI turbo applications. But if the dealer (Hyundai) literally is advertising carbon cleaning as a service for their own GDI turbo application clearly the problem still persists with the cars their manufacturing lmao. This motor has been around for almost a decade. If it was as simple as installing a baffle into ICE's then automakers would have done that long ago. Then you wouldn't need carbon cleaning for your VW or your Hyundai...it's not that simple. For some reason, you want to discredit catch cans. You don't have to agree with anything I have to say that's the beauty of free speech. You can do whatever you want with your vehicle, that is the beauty of freedom. But saying that I'm trying to convince you that catch cans are necessary because of past info is again incorrect. That's like 7 false statements in a row my man. You don't have to be sensitive because I have a different opinion than you lmao. Like I said I presented my finding and that's it. *Kanye shrug
 
Awesome video! Check out the 12th minute. Oil/water separators built in the head covers. Whether you add an external or not is up to you. But the engine most definitely has them.

I will again give you more facts lol. @R Veloster N . Check this video as they explain components of the Veloster N. He states that the air/oil separator in these cars was installed as a method to prevent oil from spilling out of the engine cover during track applications. He did not mention that it was to mitigate carbon buildup. Will it? Possibly, I would hope so. But he states to the best of his knowledge the piece was installed to mitigate oil spill. I also purchased similar components (pcv plate/ catch can) for my MK7 GTI application. The main reason for the aftermarket pcv plate and catch can for the MK7 GTI platform was to mitigate oil pooling during track applications (such as hard braking) as well as carbon buildup. Furthermore, below are your pictures of carbon buildup on our Theta II Turbo engines both on the pistons and valves from a boosted application. It doesn't get more obvious than this. It doesn't seem "negligible" to me. This picture was taken at 18k miles if I remember correctly. Lmao alright, I've made my point now. You're off the hook. Everyone simply needs to test their own motors and act accordingly. I've tested mine and I know the results I have gotten, so again please do not try and discredit my findings when you have nothing substantial to add of your own.

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From the above post, you had a catch can in your GTI How much oil per 1000km did the catch can in your MK7 GTI accumulate?

In your VN you had 15mL in 3000 miles = 5mL/1000miles.
 
From the above post, you had a catch can in your GTI How much oil per 1000km did the catch can in your MK7 GTI accumulate?

In your VN you had 15mL in 3000 miles = 5mL/1000miles.

I never personally recorded oil levels of catch can results on my MK7 application. It was substantial but never documented. Also the can I was running in that application would also capture substantial wator vapor. At the time I was too lazy to determine how much was oil and how much condensed vapor lol. The results I posted regarding my VN are per 1000 miles. So it's 15ml in 1000 miles, 45 ml in 3000 miles.
 
I'm not contradicting anything I've said. You're simply taking issue with what I've said on your own terms. You're presuming far to much and know very little about what your addressing with me personally.

I'm not going to attempt to justify to you my personal thinking, as you'll continue to take issue and find fault where there is none. This is your present methodology. There is no argument here however, you wish to construct one.

I'll say this in closing. You have issues with the GDI in general, I don't. You are fearful of the engine obviously! Why, because of your personal bad experience. I don't agree with your analogy as you base it on one particular instance in the past. You don't have the technical data to prove what you are speculating about this particular engine.

I don't care what you do with your VN but you're not going to convince me a CC is necessary for this engine.


You're overreacting plain and simple and seriously need to calm down.

You're repeating yourself time and again. What you're referring to is simply semantics. You have no factual long term evidence to refer to with the Hyundai i30N and VN engine.

Every dealership from every manufacturer offers these services. Hyundai is not the only manufacturer by far.

Besides you're beginning to rant and not making much sense. This is not debating. You've repeated yourself with the same information, so many times in different threads, it beginning to sound like a recording.

Observation of your personal comments have shown, you're afraid of what you own and are attempting to convince others of that same fear. You bought the car, no one twisted your arm. You have to deal with your own servicing, problems and fears.

There is no debate here, just you're personal speculation. You've written 5 successiver posts with no pertinent information, regarding the 2.0 Theta II engine. Why, because you haven't any. You might need to quit assuming other owners are not aware or informed, that you're more of an authority then they are and the only one who can read or understand.

Members on this forum are enthusiasts. They chose the N because it suits their niche and desires. It's not an imposition to them but a positive aspect in their lives. Try to leave it that way, without all the personal insistence, that it's not. You have your way of thinking and others theirs. It doesn't mean you right but your not going to convince others, by beating a dead horse to death.

You've attempted to convince someone by making 5 successive posts haven't you? It's actually become quit repetitive, from this thread to several others. Why not take a breather and calm down?

I do the maintenance regardless of your comments, insistence or otherwise. So do others. I'm not afraid of what I purchased and have no qualms about the engines reliability. I conduct preventative maintenance on everything I own, as I invested my money into it. I don't wait and ignore it, until have to spend a $700 to have the head dismantled and the valves cleaned.

So now, you're action is to overreact and convince others it's necessary to do the same. I don't need to over react, neither does anyone else. Just keep a good maintenance schedule for the car.

Keep this in mind, I have nothing to prove to you, for any reason. You don't know me or how I maintain my cars etc. I don't agree with your reasoning because, you have very few miles on the VN respectively and are speculating about something you're not aware of fully. Miles and maintenance will tell. Until then it's all speculation on your part. Enough said, as far as I'm concerned.

You've provided no information. If your're calling my attempt to use logic and my results that I have recorded ranting then I suppose I'm ranting lol. I'm very calm. You keep going back and substantially editing your posts based on how I respond so it's tuff for me to argue the points here. This is not a debate because you are not adding any new info to the convo. You're simply stating false claims such as I am trying to convince members that catch cans are mandatory or they will have a similar experience to what I did on my GTI. Neither are true. I keep repeating myself bc my position has not changed. You simply say my results are false without any logic or supporting evidence . Again lol I'm not trying to convince anyone of anything . On the contrary you are trying to discredit my finding with no logic or factual evidence to back it up. Again you continue to contradict yourself . You claim that there are no issues to consider yet you perform preventative maintenance. Don't understand your logic here yet again . I am posting multiple posts bc thats simply how my though process works . I like to break thoughts up. That's just my personal preference. And it's a bit easier to understand rather than how you go back and edit multiple paragraphs based on another members response. You keep stating I'm over reacting with using a catch can yet your doing an even more labor intensive and complicated process of chemical cleaning in order to clean your valves periodically . Catch can your just dumping your captured oil every couple thousands of miles. Chemical cleaning there's an entire process to follow. Followed by carefully babying your vehicle for a certain amount of miles so you don't get valve float and literally destroy your valves. If you don’t like catch cans or think they are effective simply state that. But don’t say that carbon buildup will not be an issue in the future with no logic or evidence to back it up. I have provided substantially more evidence than you regarding this matter. Again you are contradicting yourself . If I'm over reacting then you are doing the same lol. The fact that other dealers have carbon cleaning services as well proves my entire point so thank you for admitting that.
 
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From the above post, you had a catch can in your GTI How much oil per 1000km did the catch can in your MK7 GTI accumulate?

In your VN you had 15mL in 3000 miles = 5mL/1000miles.

So doing quick math assuming that the rate of captured oil remains the same (when in reality it should go up bc of more blow by as vehicle ages). After 60k miles I will have roughly 1/4 gallon of oil and combustion gasses (mostly oil) traveling across my valves . Whether we believe that this will cause substantial carbon buildup is still up to debate. I simply encourage everyone to determine on their own engine and based on geographic location and driving habits how much preventative steps should be taken to mitigate carbon buildup . One does not need 3 inches of carbon buildup to totally change the way that air enters the motor. My original intent was simply to record my finding with my catch can application . I will also be doing chemical cleanings every 20k miles to mitigate carbon buildup . 10k is a bit to frequent for me personally . What is a fact for my own engine in my own region and my own driving habits is the amount of oil I captured per 1000 mile intervals.
 
Furthermore, below are your pictures of carbon buildup on our Theta II Turbo engines both on the pistons and valves from a boosted application
Sorry, you're very much mistaken. They are not mine and I didn't post them.

However, I do know who did and where they come from. If you'd like a full explanation of the photos, then PM me and I'll share this info.
 
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Sorry, you're very much mistaken. They are not mine and I didn't post them.

However, I do know who did and where they come from. If you'd like a full explanation of the photos, then PM me and I'll share this info.

Was just ribbing. They are indeed not your photos. These photos come from @RPM8300 who I am sure would be more than happy to provide his insight into this issue and his experience with carbon buildup. Soon after I acquired the VN I saw his page on IG and DM'd him about possible carbon buildup issues. He has a very impressive build and was more than happy to share useful information with me. To be absolutely honest and fair (I have no problem sharing honest opinions and determinations that are based in logic and data) he did not see the benefit of running a catch can either on these vehicles on the pcv side. However I do not know all of his driving habits. We have already determined and it is common car engineering knowledge that blow by and crankcase pressure will be routed through the breather side when the car is under boost and not vacuum. The pcv side functions off of the vacuum of the intake manifold. If you are constantly under boost (racing the engine) most of the crankcase pressure will be routed through the breather side. To the best of my ability to remember our conversation without digging back through old DM's on Instagram he and his mechanic saw most blow by exiting through the breather part of our crankcase ventilation system. Thus routing blow-by through the turbo through the inter cooler, throttle body, and over the intake valves and into the combustion chamber. He claimed he had seen immense carbon buildup on these engines both on the piston and valves and that he was regularly adding gumout in his fuel tank quiet frequently. Updating my previous comment these pictures were taken at 10k miles as far as I can remember. He had boosted the turbo early on and swapped out the turbo either slightly before these photos or after (forgive my memory haha). After he went with methanol injection to combat the carbon buildup issue and for more power I assume :) . However, based on my own research and testing for my vehicle in my region under my driving conditions I have seen benefit of running a catch can on the pcv side. So basically I am disagreeing with his take based on my own experience of my vehicle. And that is quiet okay. We do not all have to agree on every topic. That is the beauty of these forums and sharing information to enlighten ourselves and others on this platform.
 
Now for a quick teaching moment for all who are not super familiar with carbon buildup issues with DI cars. My intent is to never fear monger, just to provide relevant information based on factual data and evidence. I have been accused of ranting, speculating, and not providing data or evidence so here we go with a quick explanation on my reasoning and the issues we have been dealing with in the car industry in regards to carbon buildup and direct injection.

We will start with this. Car companies have one job. To sell cars and make profit. As environmental regulations increase in an attempt to help the planet, regulations and rules have been tightened on auto manufacturers. Direct Injection motors are an attempt to meet these regulations while also delivering a better product. Direct Injection allows one to have a lot of flexibility with tuning. You can create more power, have better fuel economy, and have greater flexibility of motor capabilities on the fly. ECU's have become super fast and smart in their ability to continuously alter how a motor functions (such as timing). The trade off to DI is that there is no fuel that is washing over the intake valves to clean off any deposits that have formed on them. Port injected cars still have to vent crankcase pressure from blow by. Back in the day blow by could be vented right to the atmosphere. Meaning you never had to deal with the junk coming out of them. As regulations have tightened this blow by has been rerouted back into the intake stream to be re burned in the engine. This means that our crankcase ventilation systems were an AFTERTHOUGHT. Thus, one gets carbon deposits that form on the intake valve from the gunk that is coming from the crankcase. Deposits cool on the intake valves and eventually cake and build. While a port injected vehicle would use gasoline to wash away small deposits from ever forming this is not the case on DI vehicles. This is not a Hyundai issue, this is not a Volkswagen issue this is an INDUSTRY issue. It is simply the technology that is flawed. Plain...and simple. Car companies do not promote the downsides of this technology because why would they? There job is to sell cars. A brand new DI engine has more power and better fuel economy. Why would you advertise more maintenance? In the American market a lot of individuals do not notice or deal with these carbon deposit issues as most Americans only keep their vehicles for 2-3 years on average. This is evident in the way that Volkswagen sells its Golf vehicles. In america we only get DI. We still get the power and fuel efficiency but the drawbacks of carbon build up. In the European market the GTI's have already switched over to both DI and Port injection. A concept that the largest auto maker in the world made common...Toyota. Europeans tend to keep their vehicles for much longer time frames in relation to Americans (silly Americans lol). The benefits of running both DI and port injection is simply not just cleaning off intake valves. You can perform even greater tricks with timing, cooling, fuel efficiency etc. But a huge benefit is having no carbon deposits to deal with.

Now to move onto the evidence. I encourage everyone to do their own research. Please please do your own research and testing. Do not rely just on my words or anyone else's on any forum. Below is a video from EngineeringExplained on Youtube. He quotes a Society of Automotive Engineering experiment that measures the amount of carbon buildup on intake valves from blow by and crank case ventilation. The results were obvious. As you route the crankcase ventilation system to atmosphere carbon deposits are significantly decreased. Thus, using a catch can keeps your emissions in check but also can significantly reduce carbon buildup by capturing oil particles that would otherwise blast the intake valves. He also mentions just like me that catch cans are NOT a cure all. They simply help to mitigate the issue at hand.


Next, this is another video from savagegeese. He is very informed and has a very nice channel on youtube. He completely explains direct injection, why it was invented, drawbacks, and how to prevent them. He specifically mentions carbon buildup on GDI cars as a HUGE issue in the INDUSTRY. I highly recommend watching all 20 minutes of this video as it is very informative. He includes multiple sources and diagrams from large scale automakers such as HYUNDAI/KIA. At the 6:38 mark he explains the issues with direct injection and how blow by gasses cause carbon buildup on intake valves. At 12:52 he speaks on the benefits of using catch cans to mitigate blow by gases that are funneled through the pcv system.


Moving along... here is a description of the services that Hyundai still utilize to clean carbon buildup off of their intake valves and throttle bodies to this day. I called 3 different local dealers in my area yesterday and asked to speak to the service managers. All 3 service managers claim that even though carbon buildup issues have been getting better and better this is STILL an issue found with all of the GDI engines that Hyundai produces. They offer chemical cleaning service to clean the intake valves. They recommended I come in for service every 30k miles to ensure that carbon build up is not an issue. The logic behind this is that if you wait until 60, 80, 100k miles there will be so much carbon buildup that you will have to do a manual cleaning. Even if you factor in the thought that dealers are scammers and are trying to take my money every 30k one would assume its prob in our best interest to get our valves chemically cleaned every 60k miles or so at a MINIMUM. Additionally there is a video where a Hyundai tech shows how they perform the chemical cleaning. I also mentioned that I have a VN and they saw no reason why this vehicle also would not develop carbon buildup in its lifetime.

https://www.tampahyundai.com/service/fuel-induction-service.htm


Finally there is another mentality as to why carbon buildup occurs on motors. It is the mentality that oil slips past the valve stem seals and creeps down the valves onto the top of them. Thus, coating the valves and caking on carbon of the valves. As any engineer would know nothing designed is perfect or durable for an eternity. It is my understanding that all valve stem seals leak at least a tiny bit and only leak more as they age. You can find a Valvoline article that explains this concept below.

https://team.valvoline.com/diy/truth-behind-carbon-buildup

Finally, using logic lets assume that the Hyundai air/oil separator installed is relatively effective. We already know to the best of our ability that it was installed to prevent oil from leaking out of the engine cover during track days. We can see by the video posted below at the 12:00 minute mark that the intent was for track use, not carbon buildup mitigation. Can it be used for this as well? I would hope so. But I have already proved on my own setup, under my driving conditions, in my geographic area that I still capture a SIGNIFICANT amount of oil in my Mishimoto catch can. Every 3000 miles I capture roughly 45 ml. Over a 60k miles that's roughly 1/4 of a gallon of oil that will flow over my intake valves back into my combustion chamber. So again this OEM oil/separator is not perfect by any means.

I simply posted my results for my own application in both this forum and the American forum to share information. I am not jaded by previous experiences with GDI Turbo applications. I am presenting information and evidence to back up those facts. It is not a matter of IF our VN's will get carbon buildup its a matter of WHEN. If you plan to sell the car in under 5 years I wouldn't worry about it. If you just want to wait till the carbon gets really bad (stuttering, poor motor performance etc.) you can do that as well and just get it cleaned when the time has come for $500+. But if you want to jump ahead of the issue a catch can is a GREAT CHEAP tool to utilize. I have never claimed that one HAS to have a catch can or it is the end all be all. I still plan to have my valves cleaned at 30k or 40k chemically. I think for me anything before that is too labor intensive. I know I have also bought myself some time by running a catch can and emptying its contents. Please everyone do your own research and test your own vehicle. I am just offering my opinion, findings, and literature to expand upon this topic. So I say all that to say the amount of oil I have been capturing is NOT negligible @R Veloster N . There is too much information out here on the web that shows carbon buildup has been an issue for years. It is too naive to believe this issue has magically been solved by Hyundai JUST for our cars lol. I know we love our vehicles but facts are facts and we must be unbiased. Especially when Hyundai is STILL chemically carbon cleaning there cars. Perform your regular maintenance, use high grade synthetic oil to mitigate the oil breaking down and flowing over your valves, use fuel cleaner to keep your injectors clean, and finally high grade detergent gasoline (93) to assist in keeping you fuel system clean. Chemical Carbon cleaning is NOT regular maintenance in the sense of changing an oil filter, air filter, or your oil. To my knowledge it is not mentioned in the user manual. Again car companies are not going to advertise that one has to now pay someone to perform an expensive service if one is coming over from a port injected car where no such service is needed. They are trying to sell motors, and cars. More power, better fuel, smaller surface area etc. but they will not tell you up front about carbon issues. I hope someone can learn from this info! Good luck!!!
 
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Chemical cleaning there's an entire process to follow. Followed by carefully babying your vehicle for a certain amount of miles so you don't get valve float and literally destroy your valves
This is incorrect. I have done numerous valve cleanings, on many engines in the past 3.5 decades. So, I'm very familiar with the entire process. There is no babying (as you say) the engine for any length of time. However, you must change the oil @ 1500 miles after the service is conducted.

Decarbonizing all types of engines, has been around for decades, not just for GDI's. Service for GDI's is recommended at 15K intervals, not 10K as you have stated previously on several occasions. No one mentioned 10K servicing. Decarbonizing, or decoking is a standard practice with both 2 cycle and 4 cycle engines alike.
Engine decarbonization demystified; as the name suggests can be a chemical or mechanical process where carbon deposits on the cylinder head, and on the pistons are removed to ensure better functioning of the engine. It also involves getting rid of the carbon deposits from the other working components of the engine.
It's a normal practice and maintenance for others as well as myself. Trained mechanics like myself, have been utilizing decarbonizing in racing motorcycle engines both 2 and 4 cycle, as well as both automotive and reciprocating aircraft engines. It helps to recover lost power in older engines. It's considered preventative long term maintenance in all cases. I've been doing so for more than 4 decades.
Was just ribbing. (I call it; a purposeful misrepresentation or lie) They are indeed not your photos. These photos come from @RPM8300 who I am sure would be more than happy to provide his insight into this issue and his experience with carbon buildup.
No, they are not of RPM8300's car. Again, you are very much mistake. It's of another VN from an owner in South Korea.

The car has over 12K miles as of these specific photos. It's utilized in, daily stop and go South Korean traffic, as well as being tracked regularly. Something I'm very familiar with in South Korea being a retired soldier.

The owner has been utilizing a cheaper grade Shell oil. The carbon build up is normal, not abnormal or unusual by any means or definition of the word.

Excessive heat, is one of the primary causes of carbon build up. Along with hydrocarbons from the fuel, oil and condensation in the engine. Lead additive type fuels will build up carbon deposits faster than ethanol fuels. However, ethanol in fuels is produced with water and are corrosive to engine parts. This water/condensation will cause internal corrosion of internal engine parts, in high enough quantities and over time, which contribute greatly to carbon build up. It's simply a byproduct of ethanol fuel use.

The higher the ethanol content the more corrosive to the engine, especially E-85.
Over a 60k miles that's roughly 1/4 of a gallon of oil that will flow over my intake valves back into my combustion chamber. So again this OEM oil/separator is not perfect by any means.
Which if allowed recycled thru the PVC system and re-burnt in the combustion cycle, will reduce this particular speculated amount by over half.

Note: Normal combustion, will burn oil up to an acceptable level of 1 quart every 1500 to 2000 miles.
It is a fact, that most engines will burn some oil. The majority of manufacturers consider one quart of oil in the range of 1,500 miles to be acceptable.
It varies, depending upon age, internal wear and is not isolated to GDI engine alone. Over a lifespan of an engine, this oil consumption amounts to far more than a 1/4 of a gallon in 60K miles.

So, what you've shown or attempted demonstrated are negligible amounts. Especially in direct comparison to oil that is burnt in normal combustion, over the engines life cycle.

Fuel/Oil/water/condensation vapor cause carbonizing, and originates from combustio blowby and the crankcase, not just in GDI but all engines and certainly not to the amount you're speculating for this engine. You simply have not taken in consideration, normal oil consumption, wear (longevity ) & tear along with, keeping a proper maintenance schedule.
If you just want to wait till the carbon gets really bad (stuttering, poor motor performance etc.) you can do that as well and just get it cleaned when the time has come for $500+. But if you want to jump ahead of the issue a catch can is a GREAT CHEAP tool to utilize. I have never claimed that one HAS to have a catch can or it is the end all be all.
You just did, again!:p You're telling everyone and suggesting that a CC will solve the coking issues, along with a 30K-40K chemical cleaning. You don't know. This statement is supposition.

You haven't done any borescoping of your own engines; intake valves or piston tops, (ie like @LateralGrip) has to provide verifiable proof of what you're claiming and speculating about. No comparison from 3K miles till now. So, what you've submitted is hypothetical supposition, in reality.

Alternatively, you haven't done a side by side comparison of this specific engine (yours in particular) with and without a catch can being utilized, over the long term. All you done, is shown what you are collecting in your catch can and Oil lab analysis results.

You have no first hand proof, with this particular engine and in reality don't know. You've simply plagiarizing the information provided by the internet and internalizing it. You really don't have any practical experience.

Your insistence to others, a catch can is a viable alternative is; farcical and unfounded.
I will again give you more facts lol. @R Veloster N I also purchased similar components (pcv plate/ catch can) for my MK7 GTI application. The main reason for the aftermarket pcv plate and catch can for the MK7 GTI platform was to mitigate oil pooling during track applications (such as hard braking) as well as carbon buildup.
From the above post, you had a catch can in your GTI How much oil per 1000km did the catch can in your MK7 GTI accumulate?

In your VN you had 15mL in 3000 miles = 5mL/1000miles.
Thanks to @Davo01 for also pointing this out.

You didn't answer Davo0, because you didn't have any data then or now.

Even after the inclusion of a PVC catch can on your VAG engine, it still didn't mitigate the need for a manual decoking/decarbonizing @60K miles and $700+ dollars later. So once again, what you've offered is invalid, by your own previous comments and admissions.

This is exactly what I have observed, you have comment too and are attempting to convince others of.
 
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This is incorrect. I have done numerous valve cleanings, on many engine in the past 2 decades. So, I'm very familiar with the entire process. There is no babying (as you say) the engine for any length of time. However, you must change the oil within 1500 miles after the service is conducted.

Decarbonizing all types of engines, has been around for decades, not just for GDI's. Service for GDI's is recommended at 15K intervals, not 10K as you have stated previously on several occasions. No one mentioned 10K servicing. Decarbonizing, or decoking is a standard practice with both 2 cycle and 4 cycle engines alike.
It's a normal practice. Trained mechanics like myself, have been utilizing decarbonizing in racing motorcycle engines both 2 and 4 cycle, as well as both automotive and reciprocating aircraft engines. it helps to recover lost power in older engines. It's considered preventative long term maintenance in all cases. I've been doing so for more than 4 decades.
No they are not RPM8300 car. It's of another VN from an owner in South Korea.

The car has over 12K miles as of these specific photos. It's utilized in, daily stop and go South Korean traffic, as well as being tracked regularly. Something I'm very familiar with in South Korea being a retired soldier.

The owner has been utilizing a cheaper grade Shell oil. The carbon build up is normal, not unusual by any means or definition of the word.

Excessive heat, is one of the primary causes of carbon build up. Along with hydrocarbons from the fuel, oil and condensation in the engine. Lead additive type fuels will build up carbon deposits faster than ethanol fuels. However, ethanol fuels are produced with water and are corrosive to engine parts. This water/condensation will cause internal corrosion of internal engine parts, in high enough quantities and over time, which contribute greatly to carbon build up. It's simply a byproduct of ethanol fuel use.

The higher the ethanol content the more corrosive to the engine, especially E-85.
Which if allowed be in re-burnt in combustion cycle, will reduce the amount by over half of what you're speculating.

Normal combustion, will burn oil up to an acceptable level of 1 quart every 1500 to 2000 miles.
It varies, depending upon age, internal wear and is not isolated to GDI engine alone. Over a lifetime of an engine, this oil consumption amounts to far more than a 1/4 of a gallon in 60K miles.

So in fact, what you've demonstrated are negligible amounts, Especially in direct comparison to oil that is burnt in normal combustion over the engines life cycle.

Fuel/Oil/water/condensation cause carbonizing, not just in GDI but all engines and certainly not to the amount you're speculating. You simply have not taken in consideration, normal oil usage and wear (longevity) or keeping a proper maintenance schedule.
You just did, again! You're saying and suggesting that a CC will solve the issue, with a 30-40K chemical cleaning.

You simply don't know!

I’ve made my points so I won’t comment further. The user who I spoke with on IG has the same exact name as the member I tagged. I'm not sure why he would be commenting on another individuals vehicle but hey maybe I'm wrong lol. I am suggesting that a catch can and a chemical carbon cleaning will solve the issue? Um... I'm not sure what your getting at lol. You're saying that chemical carbon cleaning will not clean carbon off of intake valves? Is that not the point? You will have to continuously clean the valves over the life of the car. Best agree to disagree here, this convo isn't going anywhere lmao as you have again provided no outside evidence other than your word. I disagree with most of whats you said though and that's fine :)
 
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