3.3TT Spark plug replacement, help a novice out

[The_Vegetable]

Hello, first post here, for starters I apologize for bringing up yet another spark plug thread, I've looked through the various other threads and while I want to say "I know which plug to get", I really don't. (It doesn't help being on the neurodivergent spectrum either, forgive me if I'm just restating anything that's already been said in other threads.)

I recently bought my 2018 Stinger GT1 last month and come to find out the previous owner didn't do plugs when it was due, and it had the older 3 piece style ignition coils (Which were also corroded, causing a miss as well as the Audio popping issue), and figured I'd tackle it myself, but looking for spark plugs at the time overwhelmed me, and against my better judgment only replaced the coils knowing the plugs weren’t changed and possibly damaged by the old coils. Looking to tackle the plugs now, I honestly don't know which to go for.

From my understanding the OEM NGK's are dealer locked, which leaves my options as the NGK Ruthenium HX 95125 LFER7BHX, the HKS M45IL, or the Denso plugs. I understand that technically the HKS and the Denso plugs are mostly for those who are tuned, but I’ve seen in some threads that the HKS plugs could be used on a stock tune with the 0.28 pre gap it comes with?

Is it safe to say that I wouldn’t have any issues with the HKS M45IL’s at the pre gapped spec with the stock tune? I see that the newer NGKs have worked for some, and that others have had coil boot fitment issues? I’m not sure. I know that I plan on getting it tuned later, so I figured it wouldn’t hurt running the HKS and regapping later for the tune, or would that not be recommended? Some guidance would be appreciated as I get into this, I’ve always had the dealerships do work outside of basic maintenance but decided I wanted to finally get into doing things myself.

 

[Danny5]

I would just get the HKS plugs and gap them down to .024 to .025

They work perfectly on stock tune and will definitely be a peace of mind if/when you decide to mod in the future.

 

[Ohiocruiser]

I am running hks, on stock engine, straight out of package, without any problems.

 

[Dubso]

I am running Denso 5346 Spark Plug gapped to .24 Works fine with or without tune on mine.

 

[BIG-D]

I'm running glow plugs out of a Perkins diesel... sometimes it takes a while to shut down.

 

[The_Vegetable]

Thanks for the replies and reassurance. I got the HKS and gapped to .026 to see how it goes when I get a jb4 later next month. The car is otherwise running fantastic since replacement. Took me about 2 hours, but with my first time replacing plugs on a car and working under the intake, I’ll consider that job well done.

Interestingly, the previous owner at some point threw in some Denso IKH24’s that had definitely seen some life… heavy staining on the porcelain, and the electrode was extremely worn, so much so that the gap was at .055. I… genuinely don’t know how the car ran as well as it did before replacing them.

 

[BIG-D]

Pic's?

 

[blnewt]

The Ruthenium NGKs work well with the newer 1pc coil boots. I've heard the spark plug terminal doesn't work with the old 3 pc boots though.

 

[Nigel65]

Thanks for the replies and reassurance. I got the HKS and gapped to .026 to see how it goes when I get a jb4 later next month. The car is otherwise running fantastic since replacement. Took me about 2 hours, but with my first time replacing plugs on a car and working under the intake, I’ll consider that job well done.

Interestingly, the previous owner at some point threw in some Denso IKH24’s that had definitely seen some life… heavy staining on the porcelain, and the electrode was extremely worn, so much so that the gap was at .055. I… genuinely don’t know how the car ran as well as it did before replacing them.

Spark plugs are ok except that number 5
To get it back in i disassembled the coil pack into two separate pieces using white grease in went back in together without effort or issues
I gapped at 0.022. As im running on E85.. this car is not my everyday drive just a weekend rocket .

 

[Ohiocruiser]

Quick reminder. Removing upper intake manifold to get an access to spark plugs is easy job. Took me 30 min first time. Now I can do it under 10 min.

 

[Daniel @ K8 Stinger Store]

Is it safe to say that I wouldn’t have any issues with the HKS M45IL’s at the pre gapped spec with the stock tune? I see that the newer NGKs have worked for some, and that others have had coil boot fitment issues? I’m not sure. I know that I plan on getting it tuned later, so I figured it wouldn’t hurt running the HKS and regapping later for the tune, or would that not be recommended? Some guidance would be appreciated as I get into this, I’ve always had the dealerships do work outside of basic maintenance but decided I wanted to finally get into doing things myself.

Absolutely, you are safe to install and run the HKS M45IL plugs into a stock engine. I had mine in for a couple days before installing the Jb4 but you could run them through their whole life cycle on a stock car and be ok. The plugs come pre-gapped and ready to be installed, you just want to check the gap and make sure they are all correct and the same before you install.

If anyone is looking for these plugs we have them availale on our website. (CLICK HERE TO VIEW HKS M45IL SPARK PLUGS)

 

[Thomby]

Spark plugs are ok except that number 5

Just for clarity for those who find this in the future, the difficult cylinder under the throttlebody is #3:

T

Thread 'Definitive Kia Stinger cylinder numbering'

Aug 16, 2024

With the ambiguity regarding cylinder numbering on the Stinger's V6 (saw a reference to cylinder 3 on the driver's side in the oil line recall doc), I decided to disconnect the middle driver's side (right bank facing the engine bay, left bank from inside) coil pack, shown with red arrow below:



At startup it was obvious that I was down a cylinder, with the open hood visibly shaking at ~1000 rpm. Not sure if rpm was up there to compensate, or just because it was a cold start...I didn't run it like this very long. Check engine light was on, and my ODBII reader pulled a...

• Thomby
• Replies: 2
• Forum: Engine, Drivetrain, Intake, Exhaust Discussion

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[blnewt]

If you have the newer 1 pc boots that problematic plug is easy if you twist that boot 180 degrees after you get the holding nut off and bend it toward the front, not pull it out towards the back. Left the manifold on and got all plugs R&R'd in 45 minutes. After doing it now I could do all in 30 minutes I'm thinking.

Here's the tools I used (that long 3/8" extension has a wobble end), the plugs shown are the NGK Rutheniums, but they only work w/ the newer boot/coil packs.