NGK 6619 Iridium Spark Plugs LFR6AIX-11 tips melted way.

I never have seen a Iridium spark plug do this. Did Amazon send me fake plugs 5 years ago?

I have done every plug change on this truck. I'm the original owner. ended up changing to auto light plugs today on the left in photo. Best plugs in stock that i cooed get on the spot.

 

How many miles have you had on the NGK? They are supposed to last over 50K miles.

 

How many miles on those

 

I'm thinking I have 140 or 50k on them. 3years ago I got a commuter car so I only drive the truck on the weekends or to tow. Every set of plugs before always looked used but ok. I have 188K on the the truck now. I would think at some point it would throw a code or dash light

 

Those look more like copper core than iridium.
The tips don’t look right. The number matches iridium?
I can’t say I’ve seen any worn that low? You say they have 140-150k on them?
I guess that could do it.

Personally I like the Denso Std. Copper Core

 

numbers matches iridium yes. I know i do not have over 50K. my only thinking is that i got a bad set or a fake set. I have looking at fake plugs on you-tube. NGK has had a fakes hit Amazon and some parts stores. I my last plug change would put me in that time line.

 

I typically buy my plugs at the local Auto Parts store.
Not necessarily because I am afraid of fakes. But I like to inspect them before I buy them.
Nothing like opening a box and finding a cracked plug. Especially when you are in the middle of changing them.

I have heard or counterfeit plugs. I know there was a bunch of Motorcraft fakes floating around at one time.

 

My guess is they're fake.

https://www.google.com/search?clien...s+are+fake#kpvalbx=_xhz_Yd7WOayhptQPxZWVwAk22

 

I’ve seen the hook, ground electrode, completely eroded away. My limited experience with iridium plugs, I’ve never seen the center electrode eroded away like that.

I had some iridium’s in my turbo Buick for way longer than I should have without checking them. The ground electrode had carbon buildup all over except for a tiny circle across from the center electrode. Still though, the gap remained very close to what I set them at when they went in new.

My first plug change in the taco, I too bought plugs off Amazon, denso copper, and received what I suspect were counterfeits. The U groove was off center pretty badly. So the next set I bought locally.

 

Those are not iridium.

 

Last purchased Nov 28, 2017. There fake plugs. look at the photos ppl have posted

$44 NGK 6619 Iridium Spark Plugs LFR6AIX-11 - 6 PCSNEW

https://www.amazon.com/gp/product/B00IAGN4UY/

 

Stock spark plug change interval on the 4.0 V6 with standard plugs (Denso K20HRU11) is 30k miles. How much longer of an interval do you get by running those Iridium plugs?

 

I 100% agree

https://www.ngk.com/ngk-6619-lfr6aix-11-iridium-ix-spark-plug

 

Hmm those look like what I pulled off mine when it had like 60k miles on the iridium’s that came with my supercharger. So it can happen even on the real ones

 

I have no idea what the mfg recommended interval is but I’ve seen 100k interval thrown around by multiple people on this forum.

https://www.tacomaworld.com/posts/26846613/

edit: NGK says 50k. Additional reading ngk rates life expectancy 40/50k depending on driving conditions. Ground electrode wear is normal.

https://www.ngk.com/ngk-6619-lfr6aix-11-iridium-ix-spark-plug

https://www.ngk.com/how-long-do-ngk-iridium-plugs-last

 

The 30
30k thing is about emissions. Most likely the standard plugs would make 60K+ Iridium? I'll let you know got 60+ K on them now the truck is doing every thing right I'm going to yank them at 90K

 

So an extra 10-20k miles, but the Iridium plugs are more than double the price each? Where is the value proposition?

Oreilly Auto shows the K20HR-U11 is $4.99/ea,

$44 LFR6AIX-11 - 6 PCSNEW

LFR6AIX-11 is $11.99/ea.

 

Emissions is going to tie into overall engine performance. The more wasteful an engine is about processing gasoline for power, the less power you're putting to the wheels.

And 30k is convenient since it ties into service intervals for diff/xfer fluid changes, etc.

 

Yeah those look fake. I would just stick to Denso iridium from rockauto. Never had a problem from there.

 

Exactly, Tough to justify the increased price point for an extra 10/20k miles. Unless the iridium’s drastically improve mpg which I doubt, I don’t see the point. I’ll stick with oem.