PSA for Hyundai Nu engine owners: Check your ignition system!

OilMagnate

Thread starter
Messages
442
Location
Oklahoma
The bolded is total BS as well (The part about them not being able to give you one).You've just got a bad dealer. My daughter had engine work done on her 2017 Sonata, and they gave her a new 2021 KONA 1.6T limited to drive while she got hers fixed.
Agreed, but it was this dealer or two dealers with the same cruddy name and management that I refuse to go to. If I cross all 3 off, then it's a 50 minute drive one-way.
 

OilMagnate

Thread starter
Messages
442
Location
Oklahoma
The TSB says if the coils are the original type with white dots on top and no ribs on the mounting foot, they'll automatically put in four new ones if you complain of CEL coming on with a misfire code.

The OP's coils appear to have gray dots so that wouldn't apply.

Also since the engine was misfiring but not throwing a code you probably want the software update which addresses that.
The picture does make them look gray. I thought they were white so I went back and checked.

White and no ribs.

20210311_161137.jpg


They also did a "software update recall" that was somehow related to knock issues, so that's probably what was done. It misfired AFTER the update also.
 

Attachments

  • 20210311_161137.jpg
    20210311_161137.jpg
    60.7 KB · Views: 0
Messages
1,047
Location
Upper midwest
I would get the proper NGK plug from a NGK dealer and not Amazon<--counterfeit. I know for the Hyundai Kona they have proprietary NGK's. The best you can do is call NGK and talk to their tech Dept an get their suggestion for a plug # from their retail stock. There have been many Hyundai engines killed by bad Ignition coils. Also for a turbo motor you should change plugs at 30,000 miles and I would change a regular DI naturally aspirated at 40,000 miles.

I switch out coils on my Kona with a set from MSD. They look as if the OEM supplier changed some plastic color and made these MSD brand. Top quality and an exact copy of my OEM coils minus some extra windings or so to increase coil performance. I also run custom $$$ HKS/NGK plugs that are a heat range cooler, since my Kona is tuned. If it had a rad tune I would go 2 heat ranges down. Mine is mild to save my clutch since there are NO aftermarket dual clutches on the market.

https://www.holley.com/products/ign...late_model_coil_packs/hyundai_kia/parts/82694


The thing I noticed is the lower plug boot needs die electric grease (DEG). I put 2 coils on and then remembered I needed to add DEG to stop spark leak and I ripped apart the coil boot trying to get the coil back off 30 minutes after just installing them and it was almost impossible to dislodge the boot. I took a Q-tip and coated the inside of the boot liberally, so just the side received the DEG.

I know bad coils can destroy these engines, so keeping good coils and plugs is an expense you will have to incur. VW I think had some coil issues too.

.
 
Last edited:

OilMagnate

Thread starter
Messages
442
Location
Oklahoma
So who makes the OEM plugs for the NU engine?

Our 17 Tuscon GDI NU has about 13k miles on it. I'll probably change them out at 30k.

No need for the dealer to do plugs on this type of engine very simple.

Don't buy plugs on ebay or amazon they are probably fake. Get them from a parts store (ask me how I know)
Completely agreed. The factory plugs only say "YURA" on them with the part number.

I only buy plugs from Advance in-person. Nobody else comes close on price. I can get a set of NGK Rutheniums for $28 (just price match RA and pick them up as soon as you can drive there, no shipping delays).
 
Messages
2,013
This is an ignition issue, not an engine defect. The Nus, IMO, are almost perfection and I'd rate them much higher than countless other manufacturer's engines (Honda's Earth Dreams engines come to mind).

I have no defense for the Theta II fiasco or why they continued to use them for so long even knowing the issues...
The Nu engine suffers from piston slap.
 

OilMagnate

Thread starter
Messages
442
Location
Oklahoma
The Nu engine suffers from piston slap.
News to me, and I've owned a few of them. Some with 6 digits on the clock.

Unless it's "piston slap" that is actually valvetrain noise caused by shoddy oil filters. That is a real thing. But use a quality filter and it's silenced instantly.
 
Messages
4,588
Location
Central Arkansastan
News to me, and I've owned a few of them. Some with 6 digits on the clock.

Unless it's "piston slap" that is actually valvetrain noise caused by shoddy oil filters. That is a real thing. But use a quality filter and it's silenced instantly.
It is a known issue with NU engines, however has nothing to do with the issue you describe.
 
Messages
1,655
Location
MN
That's so odd, my father replaced his 2014 Accent (1.6 GDI) with a brand new 2018 Accent (same engine) and experienced this same thing about 1k miles into ownership. He was one of the first people to buy the updated car, and the dealer was really stumped until Hyundai released a TSB regarding a bad batch of plugs for the 1.6. 4 new plugs, and it's been solid for the last 60k miles.
 
Messages
77
Location
GA
Carbon tracking...explain?

"Carbon tracking happens when oil, dirt, or moisture is electrostatically attached to the boot or insulator and creates a path to ground."

Related: https://gm-techlink.com/?p=12397 The plugs pictured there are an extreme example of it. If you do an image search, you'll find lots of them with a a small line burned into the insulator like your plug I mentioned in my original post.

Also:
 
Last edited:

OilMagnate

Thread starter
Messages
442
Location
Oklahoma
Well it went back to the dealer last week and it received new plugs. I tried for NGKs, but they ultimately didn't have to give me anything, so I accepted a new set of YURAs. I just said I'll keep a really, really close eye on them (and plan to check them again before the 60K mark. They also were nice enough to install a brand new set of 4 coil packs & boots as well, without a code present. They installed the updated white dot coils with the "ribs" (see CB900F2's TSB post). The ride home was flawless. It has been sitting for several days, but I took it out for it's first real drive today...80 miles round-trip. Once again, it was flawless. It drove like a brand new car. I'm 99.9% convinced this was my issue, and am confident closing this case. If I have any issues going forward, I'll report back.
 
Messages
3,070
Location
pa
thanks for the heads-up! i see the link for bulletin is for the 2.0 engine NOT the 2.4. girlfriends 18 optima 2.4 prolly same engine, but never noted engine code + runs GREAT + uses NO 10-30 oil i put in!! unlike the POS 13 malibu 2.5 oil drinker that needed a radiator + water pump with only 60 thou on it, gladly traded before the problematic wheel bearings failed!!
 

OilMagnate

Thread starter
Messages
442
Location
Oklahoma
thanks for the heads-up! i see the link for bulletin is for the 2.0 engine NOT the 2.4. girlfriends 18 optima 2.4 prolly same engine, but never noted engine code + runs GREAT + uses NO 10-30 oil i put in!! unlike the POS 13 malibu 2.5 oil drinker that needed a radiator + water pump with only 60 thou on it, gladly traded before the problematic wheel bearings failed!!
The 2.4 in your girlfriend's Optima (I'm 99% sure) is a Theta II. Totally different. You have worse problems to worry about than the ignition system 😬.
 
Messages
469
Location
Holly Springs, NC USA
A lot of dealers don't know much about the cars they sell and service. I guess the best techs can make more money going out on their own which makes sense because they don't get stuck with a bunch of low paying warranty work. The fact that your dealer didn't know Hyundai has moved some of their lineup away from GDI says a lot about their competence and none of it is very good. Also LOL at the dealer saying you need to run 100% gas. E-10 is fine and all you can get in most places. I have to seek out 100% gas for my outdoor power equipment. Even that stuff runs fine on E-10, it just doesn't store as well as pure gas.

FWIW, I changed the OE NGK plugs in my Soul which has the GDI (no turbo) variant of the 1.6 Nu at 105,000 miles. All of the plugs looked perfectly fine and the gap measured within spec for a new plug. I could have put those plugs back in and run them for a very long time. I would try to get NGK plugs if you have problems again, and try new coils if that doesn't fix it. I work in IT and deal with the same crap on warranties... sometimes the hoops you have to jump through cost more than just replacing a relatively inexpensive part.

Another dealer screwup: One of Hyundai's recalls for fires was due to dealers re-using one time use parts on GDI engine replacements, even through the service procedures were clear about the parts that needed to be replaced and installation procedures including torque specs.
 
Messages
15
I have a 2017 Kia Forte with the 2.0 Nu MPI engine. Recently it would start misfiring and the CEL would come on. If I gave it some gas it would start to run normal again and the light would go out. I took it to the dealer and they replaced replaced the coils under warranty. Code PO303 showed a misfire on #3. It's a known problem. It has been running great ever since.
 
Messages
7,621
Location
California
I have never seen yura plugs - the shells look like Champion though. Here’s what I found:


looks like Yura was the Korean affiliate of Champion and Beru(both are Federal-Mogul/Driv brands). Hyundai did use Champion many years ago.

 

OilMagnate

Thread starter
Messages
442
Location
Oklahoma
I'm actually glad this thread was revived. I'm still problem-free, but I've learned a few things. I have ultimately decided I do not trust these YURA plugs at all. The new ones have been flawless, but I'm 'losing sleep' doubting them. Ultimately, I decided about two weeks ago that I need to buy a set of NGKs to keep in the glove box, along with a ratchet, extension, spark plug socket, and 10mm. I fear these will leave me on the side of the road somewhere, so I'll have everything needed to swap them on the spot.

Guess what? NGK doesn't make a plug for the 2017-2018 2.0L Elantras. Weird... Only YURA, Bosch, Autolite, and Champion make these plugs. So I initially said "Bosch it is." But I refused to accept that NGK would just skip over one of the most common cars on the road.

So I did some digging. The 1.8L of the previous generation (2013-2016) Elantra is nearly identical to the 2.0L engine in the 2017-2018 (and I think 2019) Elantras, except for the 2017+ having Adkinson cycle and a longer stroke. So I drew the reasonable assumption that the spark plugs are identical, and bought the NGK 9723s (only because I price matched RockAuto at AAP, and only because the entire district didn't have a set of cheaper and superior Ruthenium plugs). I'll swap them in when I get time and see how they perform. I'll report back ASAP.
 
Messages
5
Location
Pine Grove, PA
I have a 2012 Elantra with a manual tranny and at 345K have never needed to add oil between changes. Using TGMO at 10K intervals, or I was while using it as a highway commuter, now it mostly sits so I'm not really sure how I'm going to handle oil changes. The only problem I've had with the car is if I start it from cold and only run it for like less than a minute, say moving it to another location in my driveway, and then let it sit, the next time I start it is a problem. It cranks but doesn't start. Takes some sputtering and stalling and cursing but it finally always starts. So I avoid the situation which is sometimes annoying. Otherwise best drive train I've had in a vehicle.
 
Messages
217
Location
California
Had a misfire a while back on my '16 Sonata Hybrid and replaced the #1 coil. This car had the ignition coil recall performed when new, so it's surprising that one coil failed. The plugs were previously replaced with Champion plugs and they're still working fine. I would have bought NGK plugs as it had from the factory, but I couldn't find any aftermarket ones online and the dealer wants $25 a plug.
 
Top