Thank you for a very informative article. This information will send shivers down the back of all Hyundai GDI engine owners.

It is possible that all manufacturers of GDI engines may have issues with the GDI injection system as VW and others are now using multi-point in conjunction with GDI injection. (8 injectors)

The fact that Hyundai engine design is mainly to blame does not let the GDI system off the hook.

 

This sucks. I have a 2015 2.0T GDI sonata. These engines will be on the Genesis G70 as well and I am hoping to buy that car next. I smell another class action lawsuit for Hyundai.

 

Yes, very disappointing article.
I fully expected to get 200k miles out of the car as I have done with my previous cars.
Looks like I may be getting rid of my 2015 when it clears 100k miles.

 

Have they fixed the design flaw? Are they still putting flawed engines in cars in 2018?

Hope you are wrong, for the dealers sake. One dealer in my are offers 20 yr / 200K power train to original owner. Another offers lifetime power train.

 

I view that 20/200k as a sign that car buyers are doing their homework and are increasingly aware of the potential engine issues with Hyundai/Kia.

It's a smart move to get over the engine issue concern as most buyers don't/won't keep a car 10 yrs let alone 20 yrs, but for those that do or rack up high miles it would seem to be a great deal .

 

Before assuming that this is 'the answer', one thing needs to be considered. If this is a systemic design flaw as serious as described in the article, then why aren't more of these engines failing? Yes, its true that quite a few have already failed, but certainly the percentage is not even close to 50%. One would expect that a design flaw of this magnitude should take down most of them. So that makes me believe there must be something else going on with these engines, such as oil pressure/flow rate being too low in the failed engines. But that's JMO, FWIW.

 

Mine just turned-over 145k mi...the 1st & 2nd owners put on a ton of miles! GLS "Great Little Sedan"! :wink2:

 

Does this article only include vehicles in it's country? A country that has such questionable quality fuel, oil that the manual suggest additives. Maybe this is more of a case of the engine being more sensitive to what goes in it than a major design flaw?

 

Challenging conclusions using facts and logic is a great skill. But why should one speculate and make guesses, instead of going to ... err... reading the "source" (Google Translate does a reasonable job: https://goo.gl/LkD2Ta )? That would have answered your concerns (at least within the scope of the article):
1.

"In 2010, when the GDI engine was found to be seriously loaded with serious defects, it was discovered by Hyundai Motor and several internal improvements were made. As a result, Is limited to engines manufactured in the United States for a certain period of time."

While the interpretation of this translation could be subject to discussion,
At the very least, the problem includes the cars manufactured (and hence used) in the US.
But, of course, low quality fuel can contribute too (and thus exacerbate the problem), even though it is not the primary culprit.

2.

"No.1 cylinder is almost free from scratches due to cooling flow and natural cooling. Cylinder scratches occur first in cylinders 2 and 3, and then to 4 in time. ""

There is a surprisingly clear explanation of how cylinders #2 and #3 (and eventually #4) get "scratches", but not #1 which gets better cooling (read it using the link above).

For what's worth:

Park said, "As a result of the investigation of 56 Hyundai cars equipped with GDI engine, serious scratches on the cylinder have occurred without exception." Hyundai Motor has been aware of this problem since 2010 when it started to install the GDI engine, But did not report it to the government or inform the consumer. "

-----------------------

To me, it is very interesting that several problems of the automobile industry are caused by overheating of the components. It took Nissan years to figure out the culprit for their CVT problems (after several years of denial, and then several more years of not knowing how to deal with it). A few years ago, they presumably solved (?) it by adding a dedicated CVT cooler.

 

The vast majority of people do not check the dipstick. If this car was in the 70s where people checked often, it is likely there would be less seizing since people would catch the low oil level and top up. Am curious if Hyundai maintains data around what the engine oil level was when the engines seized, and if dealers capture this as a data point when the car is towed in.

 

If the oil level were the primary culprit, you wouldn't have had cylinders #2 and #3 getting all those scratches first (and preferentially).
See the article translation (see the link above) and see the images there.

With the amount of moving parts in an engine, who knows where each one of these came from and/or which exact manufacturing facility created them. For example, there are many small machining shops or de-burring shops that do the final processing for various items such as fan blades, screws, blocks, pistons, crankshafts... etc. Some of these things (especially in aeronautic industry) require constant calibration and superb quality monitoring that, as mentioned above, is probably not within Hyundai's target price point. [\QUOTE]

The same as above, it were a problem with the processing, you wouldn't have consistency in which cylinders fail.

We know the engines are seizing. Hyundai has claimed it's due to manufacturing processes restricting oil flow but they're not saying (whether they don't know or know and won't tell) exactly which component is creating the failure. There have been posts by someone who has torn the engines down and cylinder 3 bearing seems to have excessive wear and fails. So it could be poor oil flow to that specific spot in the engine during whatever operating scenario or if some person/robot had a bad day making whatever upstream or downstream component. Hyundai has obviously made a decision that it's cheaper to just replace the engine than to chase down every affected one and replace the problematic part(s).

Read the article provided by the OP (see the direct link to the translation). It gives very useful insights in what is happening.

Challenging conclusions using facts and logic is a great skill. But why should one speculate and make guesses, instead of going to ... err... reading the "source" (Google Translate does a reasonable job: https://goo.gl/LkD2Ta )?

Once again, thank you @ranelari17 .
This article provides much more solid information then non-systematic anecdotal accounts (even though those also contribute to the pictures).
Of course, it is what has been figured out so far... It might not be the last word in this story though... There could be more things that would become apparent on the engines where the overheating issue is fixed.

 

With the amount of moving parts in an engine, who knows where each one of these came from and/or which exact manufacturing facility created them. For example, there are many small machining shops or de-burring shops that do the final processing for various items such as fan blades, screws, blocks, pistons, crankshafts... etc. Some of these things (especially in aeronautic industry) require constant calibration and superb quality monitoring that, as mentioned above, is probably not within Hyundai's target price point.

We know the engines are seizing. Hyundai has claimed it's due to manufacturing processes restricting oil flow but they're not saying (whether they don't know or know and won't tell) exactly which component is creating the failure. There have been posts by someone who has torn the engines down and cylinder 3 bearing seems to have excessive wear and fails. So it could be poor oil flow to that specific spot in the engine during whatever operating scenario or if some person/robot had a bad day making whatever upstream or downstream component. Hyundai has obviously made a decision that it's cheaper to just replace the engine than to chase down every affected one and replace the problematic part(s).

There have been a number of posts also saying their engine fails just outside of the warranty or corporate denies replacement due to some reason. A warranty is not a guarantee so they should be taken with a grain of salt. If either/both my cars that have the affected engine make it close to 120k, I will have zero qualms about getting rid of the vehicle just before that runs out or if it starts having other major issues I can't address. Hyundai's are pretty decent value for the price and I have zero brand loyalty. At the end of the day, it's just a tool to get you from A to B.

 

Good thing I have lifetime powertrain then. Def will avoid KIA and Hyundai for my next car purchase.

 

Keep in mind there is a certain degree of consistency with respect to the problems reported as well as with the testimony of the whistle blower and the Korean article:

- issues predominately with the internal cylinders and crank bearings, a number of years back (pre recall) there were engines failures caused by heat in the internal cylinders causing the spark plugs to break apart. Heat in the CC above a certain level can cause pre-ignition, in some cases so called super knock with devastating results.

- Whistle blower also claims engine issue are a result of a design defect, and claims to have been in meetings at Hyundai where concealment measures were discussed.

- Hyundai is currently being investigated by the NHTSA for failure to disclose a known safety defect. Opened close to a year ago but these investigations can take several yrs to conclude.

And Hyundai to me is being very tight lipped, but that is to be expected in the midst of an investigation, save for execution of the recall there have been to my knowledge no advisory to owners to check oil more frequently, recommend premium gas, use the latest overpriced ngk plugs or recommend use of syn oils. To do so could be possibly interpreted as an admission of engine issues beyond the cleaning process explanation - which at this point - well draw your own conclusion.

 

*What part would using premium gas address in minimizing these negative affects ?

 

Yes... And we are all trusting a "world renown" source called Autoherald to provide an expert analysis on why these engines are failing. I really don't know whom to trust less now; Hyundai or Autoherald.

Sent from my SM-G930P using Tapatalk

 

Yeah good point - I certainly have no idea regards the credentials of Autoherald and how credible a source they are - but I did read reports from credible journalistic sources that a good number of South Koreans were/are pretty irate at Hyundai and some of the reported missteps and attempts and problem denials for vehicles S Koreans were driving and the result was Korean court orders to recall and fix defects.

In the USA with the engine issues classified as a safety issue and requiring a recall - Hyundai would appear to be in a precarious position if it turns out that they misled as to why the engines have failed and a number of cases seized. But if the Autoherald article is accurate in that several fixes were implemented that hyundai thought would fixed the problem - they took a big risk in sticking to their cleaning process story - sometimes engineers can say -" oh yes this later revision absolutely should fixes the issue" only to see failures, albeit to a lesser degree continue.

 

Autoherald is just a theorizing article.

The debris issue was only on the '11-12 models. By '13, a new cleaning process was supposed to address it. Obviuosly, the '13-14's were also failing, so it wasn't a debris only issue. Most failures that I've seen were 'sludged' engines or no-oil engines. I've seen a few engines that failed before the 1st oil change.... most likely oil starved by debris in the oil passages. So, I don't see debris as an issue on 50k+ mile engine failures. Pretty much most of the engine issues I've seen were cause by the owners!

Issue is nothing new and Sonatas, Optimas, Santafe's.... with the GDI 2.0T and 2.4, that are failing too often. Class actions have already settled and those of us with possibly bad engines have an extended warranty and less dealer hassle engine replacement.

I've never had temperature issues with my engines. So, unless there is some low quality fuel, or a defective pump/thermostat...., I don't see it as a temperature problem. While checking the oil level EVERY week, glance at the recovery/overflow coolant/antifreeze bottle and make sure it stays full.

Scoring/galding/scuffing of the ring to bores can be caused by lubrication issues. So, oil is either non-existent or not thick enough to protect. Remember that when using the Automakers best-mpg thin oil recommendation, and/or when you never use the dipstick.

GDI blowby---- raw fuel washing down the cylinders
GDI blowby---- raw fuel thins oil so oil film is thinner, doesn't protect, and cascades since thinner oil is easier to wash away off the cylinder walls. Driving style determines if fuel gets vaped off by the PCV valve system.
GDI soot--- is like blasting media and is coking up in the rings... possibly scratching the rings and cylinder walls
GDI soot--- Hyundai's oil filter media micron rating is pathetic so its not being removed effectively enough

oil level--- how many of you check your oil at EVERY fuel fill up, top it off, and keep it to the full line/dot? weekly? or commonly NEVER!
oil change interval---- if your OE filter doesn't catch GDI micro-soot, than the only other option is shorter oil change intervals or better filters, or both for effective removal

oil viscosity.... easiest way to control fuel loading of oil is to change the oil.... see the severe service interval in your owners manual
oil viscosity.... owners manual offers more choices. So, step up to a thicker grade in case your driving style, or fuel chosen, causes dilution. Use a 5w30 in the 2.4GDI and a 5w40 in the turbo.

fuel chosen... in a perfect world, that (r+m)/2 USA 87 octane is supposedly good enough.... No way would I even consider anything but premium in the turbo. And, my octane follows the seasons for my 2.4GDI, which loves premium during summer months, gets midgrade during spring/fall, and I turn into a cheapskate regular fuel during the winter. This prevents the knock sensor from controlling your fuel delivery.

Plenty of engines failed from bearing wipe out. But, since issue is also oiling related, I would wager that the bearing failure and cylinder scoring go hand in hand. Its expected when oil protection fails, whether its fuel soaked oil, debris loaded oil, or no oil.

My 2.0T recommendations:
Minimally two oil changes a year, every 3000 miles, whichever comes 1st, with a 40 grade, preferably synthetic, oil, always using a quality synthetic blend or synth media oil filter, with a full oil level always, and using 91+ USA octane fuel(area dependent). I have 92 and 93 around here.

My 2.4GDI recommedations:
Minimally 2 oil changes a year or every 3750 miles, whichever comes 1st, with a 30 grade motor oil, using a quality oil filter, with full oil level always, using the best fuel that you can afford, and seriously considering adjusting octane for average weather conditions.

Both engines deserve toptier fuel and/or occasional PEA-based or known quality FI cleaners(a bottle or two every year).

Carbon/IVD/CC cleaning.... since water injection isn't feasible for all, use one of the vacuum or spray can IVD/CC/carbon cleaning every year or two or every 15k-25k miles. This will help maintain peak efficiency and hopefully reduce carbon buildup from triggering the overactive knock sensor.

There are many that will do NOTHING recommended above... and will simply whine/cry/complain about it. Its your choice to act on the issue, try to prevent it, or be stranded with a blown engine in the middle of nowhere or in rush-hour traffic.

 

Or one could simply buy a Camry, change oil every 10,000 miles and have the engine last 500,000 miles.

Check out the Mobil 1™ High Mileage – The 500,000-Mile Challenge

"The Camry was run at highway speeds for 12 months, and oil changes were performed every 10,000 miles with Mobil 1 motor oil. Engineers on the ExxonMobil R&D team monitored engine performance from mile one to mile 500,000."

https://mobiloil.com/en/article/why...ticle/why-the-mobil-advantage/mobil-1-high-mileage-guide/high-mileage-challenge

 

Highway speeds = low RPM, low torque load.
By far the easiest miles to put on a car.
If your car can't do 500,000 miles with pure highway miles you have serious issues.
I've flogged my Nissan Altima 3.5 and it's had 195k trouble free miles so far.

 

Highway speeds = low RPM, low torque load.
By far the easiest miles to put on a car.

"The Camry was run at highway speeds for 12 months, and oil changes were performed every 10,000 miles with Mobil 1 motor oil. Engineers on the ExxonMobil R&D team monitored engine performance from mile one to mile 500,000."

https://mobiloil.com/en/article/why-...eage-challenge

Nikki and her partner should have prepared better.Clearly,they are reciting from script.Exxon produces some very good oils,but,why did they use their High Mileage oil? I hate seeing tests like this that are run on a dyno in controlled environment.

Let's add to what Grady and Flemmons stated. Since the engine is at peak operating efficiency much of those miles,most of the moisture and/or fuel in the oil will be burned off.

If you are a believer in that 75% of wear occurs on start-up,how many starts has this engine seen in that time? Probably,not many.Some tribologists will tell you it is more like 80-85%.A test like this is super easy on the engine and should produce very little wear,even,on a cheap oil unlike the one used.

The average vehicle in America over a 100,000 mile span will have 20,000 Cold Crank Starts. Your average 100K vehicle is going to have a LOT more wear despite the Toyota going five times the mileage.

I find tests like this interesting,but,put the same vehicle in real world conditions with short trips where operating temps are not always seen, jack rabbit starts,stop and go traffic,ambient temperature extremes,drive it thru rain and snow,let it ingest smog,dust,pollen and salt.

That would be really interesting and much more representative of what most of us put our cars thru on an every day basis.Any oil,no matter how good, even the Group IV/Group V oils are going to get beat up in those conditions.

 

"The Camry was run at highway speeds for 12 months, and oil changes were performed every 10,000 miles with Mobil 1 motor oil. Engineers on the ExxonMobil R&D team monitored engine performance from mile one to mile 500,000."

Using Mobil 1 (a very good synthetic) and operated in the manner described, I would suspect multiple manufacturers engines could meet the 500K challenge. Highway cruising in most of today's cars has the engine at low RPM at or near it's maximum efficient operating condition. You turn a bunch more revs per mile running around town than on the highway.

 

"

Using Mobil 1 (a very good synthetic) and operated in the manner described, I would suspect multiple manufacturers engines could meet the 500K challenge. .

Hmm I wonder what Theta II bearings would look like at 500k . Good publicity for Toyota, didn't read the test but was it a v6 Camry ? Their v6 by all accounts is quite the solid engine.

Mobil pls take the Theta II engine 500k challenge, then you will have something to crow about ! :smile:

 

In order to rack up 500000 miles in an acceptable timeframe, they had to run the car on a dyno nearly nonstop. That's got to be the best scenario for oil life. Don't get me wrong, I think Mobil 1 is a good oil. Worst for oil I think would be tundra winters and frequent short trips.
Sadly, % folks who would keep their cars for 200k miles are "round-off errors" for car makers. My German-born co-worker ran his MB diesel to 450. Wow right?, but he rebuilt the engine, tranny, rear end, seats ...twice, even the radio bracket fell apart.
A problem for me is Japanese car maker refresh their design every 3-4 years, e.g. Prius. A 10 year old Prius or Civic/Camry...look so aged most would find any excuse to trade up.

 

I really like my 2.4 '15 Sonata GL and have had very few problems but will be trading before the 5 yrs or 100,000 km is up.....not a gambling man......cheers p

ps would like to know how many Sonata 2.4's on this forum have over 200,000 "miles" on them......just curious....

 

My dealership has a 2011 Sonata on showroom floor with sign saying mileage and it "still runs good". It was just shy of 500,000.

Now if they had a 2011 Sonata there with a blown engine saying "more like this in the shop" it would not be good for business. :wink:

 

No reason for 10w-30, 5w-30 OK. Do you have the NOACK numbers for these oils? Do you have the shear for them as well. Usually those are not given by manufacturers.

http://pqiamerica.com/index.html



This is the best place I know of to find the actual contents and values in oils.

 

I am shopping for a new Sonata now, so this article concerns me a lot. I wonder why there haven't been any follow up articles in the last year and a half?

 

Follow up articles unnecessary - you have all the automotive expertise you'll ever need right here on this site - assuming you can keep your sanity reading all this stuff.

I like fuelssogood perspective. Yes there have been past problems with the Theta II engine, it seems apparent Hyundai has made changes geared towards improving the reliability of the engine, it's clearly not the best engine on the market, but as posters point out gdi technology can have some issues . But based on pricing and overall value the Sonata appears to remain a solid buy.
Keep in mind on this site you see a small slice of owners - a good many who are technically astute, delve deeply into issues, express opinions, and perhaps make things seem more ominous than they are.

 

Hyundai is still considered a low-rent brand. Perhaps a value brand.
Sure Toyota is highly rated reliability-wise. But you do have to pay a premium of thousands $ for equivalent trim level compared to Hyundai.
On average, new car buyer keep their car 6 years.
The power train warranty should cover big problems.
In this scenario, Hyundai owners come out ahead.
If intended to keep a car for 200 thousand miles, Toyota owners come out ahead.
This is much better than 1970's cars which may only go to 100K miles.
So car reliability has really improved and are much safer today.

After the warranty period, the car maker doesn't really care.

 

First post as I've been lurking here for about a year.

This topic is timely for me as I have done several used oil analysis (UOA) since owning the car as new. It's my first Hyundai (see signature) and we enjoy how it performs and handles.

However it has been plagued with body creaks and pops behind the windshield headliner, but the details are for another post.

As to this topic I will share my UOA results as they may be significant.

I've done three since the car was purchased. The first was just before I changed the factory oil fill (608 miles) as a base number, the second was at 1568 miles on the engine and the third just recently with 3521 miles on oil.

I've used Quaker State Ultimate Durability 5w-20 since the factory fill.

Here are my UOA numbers for aluminum:

1st - 4 ppm, 2nd - 5 ppm 3rd - 9 ppm. The universal averages according to Blackstone Labs is 4 ppm.

This aluminum result is troubling. I've never had a number that high in all my other vehicles and the UOAs I've done. I would urge everyone concerned about the potential for premature engine wear on their GDI to get a UOA to see where they stand.

I have used Blackstone Labs ($28) for a number of years but there is also ALS which sells sampling bottles through NAPA for about $15.

I will do another UOA on this oil fill at about 5K miles and decide what action I should take. Maybe go to Quaker State UD 5w-30. I will also send this UOA to Hyundai Corporate in CA.

Hope this adds to the discussion.

 

Oh look, what bearing shows up failed?

#1 is failing also. So, there isn't just a rash of 2/3 bearing failures. 1 and 4 do fail too. Maybe its not reported often enough. So, it hasn't ever been a 100% failure with 2 or 3 and never has been. The 40k+ gdi 2.4/2.0T haven't all been dismantled for public data. A few salvage yard engines or failures isn't a large enough sample when we are talking about a million engines. Spend some time at the salvage yard or auto auctions with a stethoscope and you'll see plenty of 1 and 4 failed bearings too. I can find more sludged Hyundai's than 99-01 Toyota 3.0/2.2's back in the day.

I've been dealing with and watching this issue for years.

Temp sender is for the coolant and its a moving fluid. So, sender location is meaningless since coolant temperature is an average. Same can be said about oil/atf temp sender. There is nothing new about inner cylinder temps on 3/4/6....12 cylinder engines. And, my measurements of fluid temperatures on the Hyundai are not any different when compared to my Fords, Hondas, Toyotas, Nissans....

Sad that over maintenance/selective fluids/filters/common sense.... are all definitely necessary to make up for the bean counters. So, either leasetradein regularly and don't worry, or buy and TAKE CARE OF IT. Also have seen many failures across ALL the automakers. But like Toyota sludge, Audi unexpected acceleration, exploding GM pickup gas tanks.... seems that the world wants to put Hyundai out front with engine failures.

Most will make it past the 1st owner before the deficiencies rear their ugly heads for 2nd or 3rd owners which were the ones that filed the class actions as the 10/100 was only for the original buyers. Consumers weren't smart enough to pop the hood and check the oil level or cap to verify any oil/sludge.

You can theorize or whine and complain all you want. You either take care of it and forget about the GDI/manufacturing/... issues, or you trade it in. If you don't care for it and it fails, you have been warned so don't cry like a baby. The issues we are seeing across all automakers is caused by emissions and mpg. Thin oil and low tension oil rings are detrimental whether you like it or not.

Maybe it should be a requirement to force any prospective owner to thoroughly read the owners manual prior to purchasing a vehicle. It states in the your owners manual how often to check the oil.

And, when the engine family should excessive failures, keeping the oil level to the top is a must. The older GDI engines received a new oil dipstick which raised the oil level. That new dipstick is a great way of cheating the oil level.

A picture of my favorite engine mod on the 2.4GDI see the left side of this picture:

And, the genius Hyundai engineers replaced my disptick which is a solution to all my problems(see attached photo below).... do you want to wait for the 5.5 or 6 qt dipstick? So, keep the level to the FULL dot/line always on this POS GDI engine, and all your vehicles.

UOA data is not troubling since engine is breaking in. Once its fully broken in after 15k miles, gather some data. So, if the UOA data is troubling to you, why keep running 5w20? It is not required. Use the 5w30. And, QuackerState isn't required. So, if QS doesn't work for you, time to move away from the 'marketing' of QS with Hyundai.

 

So, if the UOA data is troubling to you, why keep running 5w20? It is not required. Use the 5w30. And, QuackerState isn't required. So, if QS doesn't work for you, time to move away from the 'marketing' of QS with Hyundai.

The shear values of QS are very good, even with heat. I didn't just pick QS I did some research as I had used Mobil1 for years. I can't lay this on 5w-20 yet.

I'm too new here to link but if you search "540 RAT Tech Facts" you'll find some good information comparing oils with testing. It's a long read but worth it.

Why is the break-in period 15K?

 

Folks trading in early are actually taking it on the chin for how much they are losing by trading for peace of mind given they are just at the initial phase of car depreciation. They have a stop loss to 120K miles covered by Hyundai, so why not use that to some extent? It seems a case of hitting the panic button to get rid of the car because of an impending issue.

On the other hand, telling an owner to do 3K oil changes, run premium gas and keep oil level at F at every fill up is expecting too much of the consumers and there is no empirical evidence their engine will still not seize. Compared to other manufacturers, this preventive maintenance will seem excessive in relative comparison. It raises the cost of ownership for materials and labor and no one wants to hang around a dealer or their indie shop for frequent oil changes.

 

I really appreciate all your inputs.

There are plenty of follow up articles in Korean newspapers. You just have to search for them in Google.


Ministry of Land report "Hyundai Motor Seta 2 engine defects, the same cause as the United States"

2017-10-11

http://www.hani.co.kr/arti/economy/economy_general/814091.html


Hyundai's "Seta II" engine broke down in a week after recall inspection"

July 27, 2017

http://www.etnews.com/20170630000249


Hyundai Motor Recalls, Design Flaws, Fair Problems

2017.04.10

http://biz.khan.co.kr/khan_art_view.html?artid=201704100600005&code=920508


Again, the translation is not perfect.


This is an excerpt from the last article,

"However, Hyundai and Kia Motors issued internal documents in 2015 to recall vehicles equipped with the Seta 2 GDi engine in the US. This document stipulates the cause of noise or damage of 'theta 2 GDi engine' as 'bearing damage due to oil film breakage'. When the oil film is destroyed, the bearing has to come into direct contact with the connecting rod. (Engine parts stick to each other due to high frictional heat) while natural scratches and abrasion occur.

Hyundai Motor cited the cause of the exclusion as: load in bearing (stiffness), connecting rod rigidity, crankpin processing quality, lubricating line cleanliness, and oil degradation. Among them, the part that calculates the rigidity of bearing and connecting rod corresponds to the area of ​​design.

Hyundai Motors also documented measures taken to improve engine flaws. May 2011 Change of connecting rod fastening method, August Applying of connecting rod plating specification, June 2012 Increase of bearing oil gap, August Connecting rod material change, Jan 2013 Crankshaft blast application, September Crankshaft material change It is said that it carried out."




Most people in Korea now know that Hyundai's Theta II engines are not reliable. However, people still end up buying Hyundai/Kia cars because the tariffs on import cars are too high. In Korea, Toyota Camry sells at a similar price point of Hyundai Azera (Grandeur) / Kia Cadenza (K7). Also, the average mileage driven per year in much lower in Korea, so people will buy new cars before the cars reach 100,000 miles mark.

As mentioned earlier, it appears that Hyundai made some changes to the engine under the radar over the years after becoming aware of the problem. However, I am still reading reports of engine failures in 2015+ models. Yes, it could be due to poor maintenance by the owner. Yes, the failure rates will most likely be less than the 2011 Sonata models. Yes, there will be some engines that make it to 200,000 miles, problem free. But even if the chance of catastrophic engine failure is less than 1%, do I want to take a chance with my kid sitting in the back seat on a highway, driving in front of a semi, with no shoulder to pull over to? No.


Also, I live in Canada, and the warranty here is only 5 years/100,000km (62,500 miles).

I used to have a bit of bias toward the Hyundai brand, which is why I still ended up getting the 2015 model despite having issues with the 2011 model.

I have zero faith in Hyundai now. I will go with a brand with a better known reliability next time.

 

artid=201704100600005&code=920508]http://biz.khan.co.kr/khan_art_view.html?artid=201704100600005&code=920508[/url]
...

This is an excerpt from the last article,

"However, Hyundai and Kia Motors issued internal documents in 2015 to recall vehicles equipped with the Seta 2 GDi engine in the US. This document stipulates the cause of noise or damage of 'theta 2 GDi engine' as 'bearing damage due to oil film breakage'. When the oil film is destroyed, the bearing has to come into direct contact with the connecting rod. (Engine parts stick to each other due to high frictional heat) while natural scratches and abrasion occur.

Hyundai Motor cited the cause of the exclusion as: load in bearing (stiffness), connecting rod rigidity, crankpin processing quality, lubricating line cleanliness, and oil degradation. Among them, the part that calculates the rigidity of bearing and connecting rod corresponds to the area of ​​design.

Hyundai Motors also documented measures taken to improve engine flaws. May 2011 Change of connecting rod fastening method, August Applying of connecting rod plating specification, June 2012 Increase of bearing oil gap, August Connecting rod material change, Jan 2013 Crankshaft blast application, September Crankshaft material change It is said that it carried out."

...

Your references cited has the smoking gun on oil film, lubrication, which is a primary cause of bearing failure.
To me it actually aligns with people's recommendation to use a high quality, synthetic oil, be conservative wrt OCI and needless to say, check oil level frequently.

 

Well the oft used adages apply to buying a Hyundai :

You get what you pay for
If something appears too good to be true it probably is

Hyundai isn't producing cars that are of equal or better quality than a number of leading competitors, despite all the feature to feature comparisons, but only a percentage of buyers purchase on features, albeit a fair number. In some other areas they just don't measure up to some of the competition, areas that involve design and component longevity may not initially seem important or make much of a difference.
But it would seem with the protracted decline in sales that more buyers are opting to choose models that may cost more but overall are better made - despite not offering the Hyundai 10/100 warranty in the USA.
And Hyundai is having put more and more incentives on their cars to move them.

 

If bearing lubrication breakdown were cited by OP's reference, do you think improving the margins of the bearing's oil film performance would *reduce* the incidence of such failures?
The fact that many failed engines, be it anecdotal, had mud oil is a "tell" from experts who sees many of them.
With >1 million affected engines in the field, operating conditions are all over the map. The law if large numbers dominates. One can only say, doing these things... will improve your chances.
It is like saying I use the best Syn oil on my twin turbos that glows red from heat. I know as fact Syn oil provides a greater margin of heat and oil film breakdown than conventional oil. But no one can guaranteed syn oil will make turbo lube failures go to zero.