New to the Forum - having some issues with my Stinger

[Ghost Grey]

Hey guys! I’ve lurked on this forum from time to time and finally worked up the nerve to sign up and start posting. I bought a 2018 Ghost Grey Stinger GT2 AWD in March of last year with 37k miles. The only mod I can tell it has is a Stillen cat back exhaust, which sounds great most of the time, but it tends to drone loudly at highway cruising speeds. I started to have misfiring issues at around 48k miles, so I changed out the factory plugs for NGKs. I didn’t gap them, and I’m starting to wonder if that might be the issue, but they worked fine for about the first 5-6k miles, then started misfiring again. Could it just be bad plugs? Did I not gap them when I should have? Any help is appreciated! Thank you.

 

[Kia Stinger]

Hey guys! I’ve lurked on this forum from time to time and finally worked up the nerve to sign up and start posting. I bought a 2018 Ghost Grey Stinger GT2 AWD in March of last year with 37k miles. The only mod I can tell it has is a Stillen cat back exhaust, which sounds great most of the time, but it tends to drone loudly at highway cruising speeds. I started to have misfiring issues at around 48k miles, so I changed out the factory plugs for NGKs. I didn’t gap them, and I’m starting to wonder if that might be the issue, but they worked fine for about the first 5-6k miles, then started misfiring again. Could it just be bad plugs? Did I not gap them when I should have? Any help is appreciated! Thank you.

Welcome aboard! And thank you for signing up. I'm glad you found us! I'm moving this topic out of the community lounge and into the main Stinger forum as it's more of a help request than an introduction.

 

[AdrianG]

At least checking the gap is always a good idea. Outright bad plugs is unlikely, but not impossible. Is the misfire limited to one or two cylinders? Or random amongst all cylinders?
NGK plugs aren't bad, but the HKS plugs would probably have been better.

 

[Ghost Grey]

Welcome aboard! And thank you for signing up. I'm glad you found us! I'm moving this topic out of the community lounge and into the main Stinger forum as it's more of a help request than an introduction.

Thank you! As soon as i posted, I figured I probably should've posted here. Much appreciated.

 

[Ghost Grey]

At least checking the gap is always a good idea. Outright bad plugs is unlikely, but not impossible. Is the misfire limited to one or two cylinders? Or random amongst all cylinders?
NGK plugs aren't bad, but the HKS plugs would probably have been better.

Not sure where the misfire is. It just misfires when the engine gets on boost. I've been driving it gingerly anyway, but when it does misfire, i back off. It only triggers the check engine light if the misfire goes on for more than a couple of seconds, which has only happened when i had the adaptive cruise control engaged and the car accelerated itself coming around a slower moving vehicle. The check engine light came on, I tapped the brakes, the engine came back down to idle speeds, then the check engine light went off after a few seconds. So with that, I only know there is a misfire, but I don't know which cylinder or how many.

 

[Snicklefritz]

it could easily be one cylinder and one bad coil pack. you got another bad plug or plugs because the coil pack or packs kill them.

 

[AdrianG]

I would pull the plugs. If a coil is bad, you may see tracking (basically burns on the ceramic insulator portion of the plug), this is how I've figured out a majority of misfires I've dealt with with other vehicles in the past. Another way to find out which cylinders are misfiring is by using a tool such as a JB4 or another reader.
If a coil is bad, you will have to replace the coil and the plug. Also, I believe bad plugs (if they are bad enough) can cause coils to go bad.

 

[Ghost Grey]

it could easily be one cylinder and one bad coil pack. you got another bad plug or plugs because the coil pack or packs kill them.

Thank you. I'll check the coil packs.

 

[Ghost Grey]

I would pull the plugs. If a coil is bad, you may see tracking (basically burns on the ceramic insulator portion of the plug), this is how I've figured out a majority of misfires I've dealt with with other vehicles in the past. Another way to find out which cylinders are misfiring is by using a tool such as a JB4 or another reader.
If a coil is bad, you will have to replace the coil and the plug. Also, I believe bad plugs (if they are bad enough) can cause coils to go bad.

I'm thinking about going with a JB4. Would it be worth it to just go with new coil packs and plugs?

 

[AdrianG]

I'm thinking about going with a JB4. Would it be worth it to just go with new coil packs and plugs?

I wouldn't just go replacing everything if you don't need to, that's a lot more money than is necessary, probably. That said, replacing the plugs with some properly gapped HKS plugs wouldn't be a bad thing. Replacing the plugs without knowing if you have bad coils is a futile effort, though. A JB4 will definitely help you track down a misfiring cylinder. Other scanners should help you do the same thing, but the JB4 is a good tool for more than just tracking down misfires.

 

[K8 Stinger Store]

Welcome to the Stinger Forum @Ghost Grey

As others have mentioned, better to go with the HKS M45iL Spark Plugs over the NGK plugs.

In all reality, if the spark plugs are not gapped properly, and are fired upon for 5,000-6,000 miles with the wrong, spark, plug gap, it can damage the tip and cause misfires.

I would double check the plugs and coil packs, and if the coil packs appear to be OK, I would replace the plugs with a fresh set.

We do offer very competitive pricing on these plugs on our website below:

HKS M45iL Spark Plugs - K8 Stinger Store

Reach out if you have any questions about products or anything we can assist with.

-David​