Spark plugs at 32,715 miles. How do they look?

I offer you this:


To me those plugs look a bit "dirty" but okay.
The threads show signs of seepage, as you mentioned they were under-torqued in the other forum.
I wonder if the Owners Manual has a shorter plug change interval because H/K knows the Yura plugs
can't be trusted for as long as (100K miles) iridium plugs from Denso, NGK, etc.
Valid points from my view. I am thinking the plugs I installed can go 100k. I see having consistent quality across the board as a Hyundai issue. My first week of ownership my brake booster was recalled. If I ever get a different car I would go with Toyota since they are more consistent with quality.
 
Why change them ? Because of "reports" ?

I would never put non-Japanese plugs (NGK or Denso only) in an Asian vehicle, for what that's worth.
Our Subaru use to come with Champions and Packard wire from the factory: and they only ran well on them.
Otherwise it was Nippon Denso - NEVER NGK for the std steel plugs used back in the 90's

Current and recent past NGK Iridium seem to be good performers.

Finewire iridium was a GAME CHANGER in ignition performance.

Autolite are good performers, just beware of rust on the non zinc plated shells on steel plugs.

Autolite Ir Sparkplug:
autolite ir.jpg
 
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The central insulator on the Autolite looks shorter to me…slightly different heat range? Hotter?
NO, it is where the insulator first contacts the nut wall was down inside that determine heat range.
We can see it. All else equal shorter would be COLDER.

The Autolite plug may have less reach. That's good, I'm not a fan of long reach in performance engines
with lambda control.
 
Valid points from my view. I am thinking the plugs I installed can go 100k. I see having consistent quality across the board as a Hyundai issue. My first week of ownership my brake booster was recalled. If I ever get a different car I would go with Toyota since they are more consistent with quality.
Here's a spark plug from my '17 Elantra with 64k miles on them. They all looked the same. I swapped them out with Bosch 9686 Double Iridiums. The OE ones looked dirty to me, but I'm unfamiliar with Yura plugs so I don't have much in the way of comparison.
 

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Here's a spark plug from my '17 Elantra with 64k miles on them. They all looked the same. I swapped them out with Bosch 9686 Double Iridiums. The OE ones looked dirty to me, but I'm unfamiliar with Yura plugs so I don't have much in the way of comparison.
Did you notice any difference in performance with the Bosch plugs?
 
Did you notice any difference in performance with the Bosch plugs?
To be honest, not really. My mileage picked up a fraction (averaging 42 hwy/35ish city), but I also replaced the coils so I can't say that it was solely due to the plugs.
 
To be honest, not really. My mileage picked up a fraction (averaging 42 hwy/35ish city), but I also replaced the coils so I can't say that it was solely due to the plugs.
What brand coils did you install? If I have issues I will just replace all of them.
 
What brand coils did you install? If I have issues I will just replace all of them.
I took the gamble and bought OEM plugs off of eBay. I got 4 for $145 or so. So far, they've been running great. Unfortunately, there's not much of an aftermarket for these coils. I know NGK makes a coil, but I decided to try these cheaper eBay OEMs first.
 
I took the gamble and bought OEM plugs off of eBay. I got 4 for $145 or so. So far, they've been running great. Unfortunately, there's not much of an aftermarket for these coils. I know NGK makes a coil, but I decided to try these cheaper eBay OEMs first.
The spare coil I bought on Ebay was OEM for $35. It did come in box with Mobis and Hyundai as the only thing I could read. The rest of the writing was Korean. Thanks for the update and hope it goes well long term.
 
No, it is from Hyundai and is a supplement that comes with the manual. I found it in my glove compartment in the sleeve with the manual. Just became aware of it recently. Dealer sold me one oil change and overfilled it. I have never been back. This car gets TLC from me. I get peace of mind it is well maintained even if it may seem over maintained to others.
The 50,000 mile reference is for a Hyundai turbo. I change my Hyundai's plugs every 25,000 mile with $125 set of 4, but I have massive heat and high boost pressures (23psi). Lucky I am a short tripper.
 
When I looked at the box I had a good feeling. It said FRAM Group IP LLC. I have great experiences with Fram products. NGK also. I just do not trust Hyundai or Yuri plugs.
Hyundai late model turbo cars OEM plugs are either Denso or NGK plugs from what I have heard.
 
NO, it is where the insulator first contacts the nut wall was down inside that determine heat range.
We can see it. All else equal shorter would be COLDER.

The Autolite plug may have less reach. That's good, I'm not a fan of long reach in performance engines
with lambda control.
Too many typos there. Must be from me trying to suffer the heatwave with no AC that killed the braincells even more than it was already killed.

Not that anyone cares, but,
Should read:
"NO, it is where the insulator first contacts the nut wall way down inside that determines the heat range.
We can't see it. All else equal, shorter would be COLDER."
 
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The 50,000 mile reference is for a Hyundai turbo. I change my Hyundai's plugs every 25,000 mile with $125 set of 4, but I have massive heat and high boost pressures (23psi). Lucky I am a short tripper.
Now that makes sense. If I go to the Hyundai website and look at the maintenance chart associated with my vin# it does not list the 50,000 mile reference. That being said I am so glad I changed the plugs. I will let the Autolites in 100k since I have a light foot on the throttle.
 
Just like any other diesel spark plug, lots of black soot. Better replace them with a high performance diesel spark plug, preferably the Powerstroke spark plugs.
 
Anything that led you to Autolites in particular? I've always been told Autolites don't even belong in weed eaters. Part of me thinks there can't be THAT much a difference when it comes to iridium plugs.

I've heard Champion plugs are garbage too but the ones I took out of my Hyundai looked fantastic all things considered.
I've used autolite sparkplugs for 30 thousand miles before my 2.5 got totaled, didn't have a problem with them at all and worked well.

Autolite must have a bad reputation from previous mistakes.
 
Those gaps look huge for 32k miles but my eyeball meter may be off. The color and carbon buildup seem to be OK for that mileage, maybe a tad rich but still OK / no excessive buildup.

Giving your car TLC is one thing. Replacing parts far before they are due, that is another thing entirely. Was there a TSB, recall, or other official word from the manufacturer? Or did you replace them based on some internet reports that you read? In this situation I might carry around a spare set just in case something happened, but I would never change plugs this early in a good-running car.
 
Those gaps look huge for 32k miles but my eyeball meter may be off. The color and carbon buildup seem to be OK for that mileage, maybe a tad rich but still OK / no excessive buildup.

Giving your car TLC is one thing. Replacing parts far before they are due, that is another thing entirely. Was there a TSB, recall, or other official word from the manufacturer? Or did you replace them based on some internet reports that you read? In this situation I might carry around a spare set just in case something happened, but I would never change plugs this early in a good-running car.
TSB is on the coils. They fail randomly. Plugs is from forum members reporting poor running conditions caused by the plugs or early failure. It happened to a retired Auto engineer. So he gave great detail in what he saw and followed with great reports of how the Autolites performed. I am pretty incompetent with repairs done is a rush (dyslexia). I tend to break things or mix things up. So I choose to change spark plugs early due to the bad rap they have on my own time schedule. It taught me what I need to do to change a coil. Now I could change a coil in 5 minutes without breaking anything. I am happy to report throttle response is improved. I used to have a lag at times. That is gone. Very happy with my choice to change early.
 
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