Possible Misfire, CEL Issue

[Paladin611]

Greetings, Friends,

I was on a spirited 30 mile stretch home from work on the tollway this evening, which my ‘18 GT has no issues with on any other day. At time of need, entering sport mode for the occasional needed pass.

About 7 miles from home, I noticed the CEL come on, but it was intermittent- whenever I hit the gas it would appear again though. When I got home, I parked it, but didn’t turn it off immediately (as I always do to let the turbos slow down). During this period of idling, it was then that I noticed the car was running with a slight shudder.

When I turned off the car and let it cool for about 10 minutes, I then turned it back on. When I turned it back on the CEL was gone and the shudder was gone. I revved it a few times, but the CEL never returned. I have a diagnostic taking place in the morning with my trusted garage. They cite the possibilities of a bad plug or coil. Has anyone ever experienced something like this with the Stinger? The car only has 52k on it and I always thought it was made of stronger stuff than this. Any ideas?? Your comments and experiences are appreciated in advance.

 

[Paladin611]

Regardless of no apparent interest in my post, be sure to swap the spark plugs at 42000 miles. The specialist did not mention this to me that last time I saw them. It turns out I was driving on plugs that were due to be swapped out 10k miles ago- and one of them was cracked! Also, the ignition coil for cyclider 3 was replaced. The garage here calls it cylinder 3, everyone else on the internet seems to be calling it cylinder 5, which it the crazy one under the intake mainfold. The fuel injectors were also filthy and needed to be cleaned. I’ll update again should that CEL return- which I doubt!

 

[See3Pee01971]

Your mechanic is correct 3 is the “bad” one ( I believe it’s from the front, passenger side 1,3,5 drivers side 2,4,6). I’m not surprised by this. Almost everyone has switched to the HKS or Denso plugs which can be 1 or 2 steps cooler. The fact is our much loved cars are prone to a LOT of heat, not great on plugs and other “things”. It’s not a problem with regular maintenance. These cars are built really well. Are you modded or completely stock? I’m assuming stock since you got that much mileage on a set of plugs.

 

[Snicklefritz]

oem plugs are fine on a stock engine. yes, 42,000 miles is the recommended time to change them. I had a bad coil pack and it kept ruining the new plug. once that was changed everything has been fine.

 

[Paladin611]

Your mechanic is correct 3 is the “bad” one ( I believe it’s from the front, passenger side 1,3,5 drivers side 2,4,6). I’m not surprised by this. Almost everyone has switched to the HKS or Denso plugs which can be 1 or 2 steps cooler. The fact is our much loved cars are prone to a LOT of heat, not great on plugs and other “things”. It’s not a problem with regular maintenance. These cars are built really well. Are you modded or completely stock? I’m assuming stock since you got that much mileage on a set of plugs.

Thanks for the reply. Yeah, I use HKS myself. With the exception of a Power Agency CAI system, the car is bone stock. I’ve contemplated the purchase of a perfmods, but I’m satisfied with its performance, and I don’t want to introduce entropy to it. The mechanic did say that it isn’t unusual to be able to “extend” the life of the plugs as long as I inadvertently did, but one will always experience the negative effects of doing so. Things like poor MPG, power loss, etc. This, along with the prospect of unreliability that becomes part of the plugs, as I mentioned, one of mine had cracked.

Going forward, I’ll be much more involved with the scrutiny of my maintenance and playing it by the book. Kia fell flat on their face for me. They should have reported the health of my injectors and plugs 12k miles ago. They failed my car. It took a small, “ma & pop” garage (that I actually favor) to set my car straight again. As a matter of fact, the mechanic who maintenanced my car said he has a friend who has a Stinger. I’m sure he’s worked on it before. I could have done this job myself, but it would have taken me the whole day. I’m glad this is over.

 

[Paladin611]

oem plugs are fine on a stock engine. yes, 42,000 miles is the recommended time to change them. I had a bad coil pack and it kept ruining the new plug. once that was changed everything has been fine.

Yeah- I’ve read about that happening to people. Fortunately, my cylinder 3 coil pack was replaced. It had so much corrosion on it that the plug underneath it cracked! I went with the HKS’s instead of the cheaper Denso’s.

 

[Snicklefritz]

even a good kia outfit is a throw of the dice. they recommended at an oil change that I should change the plugs and I did. trouble was they didn't check the condition of the coil packs obviously or they would have caught that bad one.

 

[Paladin611]

I’m bringing back this post with an unfortunate update. Even after all the drama last week and finally getting my Stinger seemingly repaired with a new coil pack, plugs, and a carbon cleaning (fuel injectors)- I just returned from home on the same stretch of highway that I was on last week when I got the CEL and went into limp mode. History repeats itself because, despite the $1100 worth of maintenance that I had done on Friday, I just got another CEL and went into limp mode.

This time I got an error from UVO. Engine Control System. I suspect this is a direct result of my using Sport mode intermittently. Same as before, I turn the car off, let it rest- the engine now turns normal and the vibrating is gone. But this time the CEL doesn’t go away. I called the mechanic and with meet with him on Friday. I’m very suspicious of Kia over this, especially after considering the few reprehensible service recalls that they have had. We’ll see what happens on Friday.

 

[Snicklefritz]

^^they will find 'it'. these cars are ridiculously complex and everything is found via scanner tools, etc. nobody can just listen or drive it and then be pointed to the problem. all the electronics and computer modules of which the stinger has no less than 33 make troubleshooting and diagnostics a looming nightmare. of course I just hope that your issues, obviously more than just plugs and coil packs, are sorted quickly. it is for this very reason that I have kept my powertrain bone stock.

 

[Oso7]

Crazy how the first thing I find in the forums is something I just got home to. I have a 2021 Stinger bone stock except muffler delete , BMS occ and AFE intakes. Car drove perfectly fine all week untill today I went to warm up my car and noticed my exhaust louder than normal & making popping noises. Didn’t pay much attention to it until I came back out the pops were still there once I got into the car I noticed the car idling really rough. Drove maybe 2 houses down from my home and the same[ engine control system “ schedule appointment with dealership] notification popped up. I’m only at 22k miles. To make it worse dealership can’t see me until next Thursday ‍

 

[Paladin611]

Crazy how the first thing I find in the forums is something I just got home to. I have a 2021 Stinger bone stock except muffler delete , BMS occ and AFE intakes. Car drove perfectly fine all week untill today I went to warm up my car and noticed my exhaust louder than normal & making popping noises. Didn’t pay much attention to it until I came back out the pops were still there once I got into the car I noticed the car idling really rough. Drove maybe 2 houses down from my home and the same[ engine control system “ schedule appointment with dealership] notification popped up. I’m only at 22k miles. To make it worse dealership can’t see me until next Thursday ‍

Wow! That’s crazy, man. This is certainly no coincidence. We have a bonafide, reproducible, quality problem here. I don’t ignore trends. I, too, experienced the same exhaust loudness, along with the rough idylling. Please update this thread with what your garage discovers. I will do the same. Good luck on your repairs!

 

[Oso7]

Wow! That’s crazy, man. This is certainly no coincidence. We have a bonafide, reproducible, quality problem here. I don’t ignore trends. I, too, experienced the same exhaust loudness, along with the rough idylling. Please update this thread with what your garage discovers. I will do the same. Good luck on your repairs!f

Wow! That’s crazy, man. This is certainly no coincidence. We have a bonafide, reproducible, quality problem here. I don’t ignore trends. I, too, experienced the same exhaust loudness, along with the rough idylling. Please update this thread with what your garage discovers. I will do the same. Good luck on your repairs!

So after being out all day I finally got home to take a look at what could be causing the issue. And after seeing a couple vids /post. I decided to do a basic troubleshoot so I started off with making sure the camshaft sensor was connected tight and BINGO it’s wasn’t lose to point where it would have just fallen off but it had a small play to it. Pushed it back in and turned the car on and it’s gone. Just came back from a bit of hard running and everything seems to be okay. I will def keep and eye out the next couple of days to see if it returns or not but I’ll keep you’ll posted man! Good luck to you as well!

 

[Paladin611]

So after being out all day I finally got home to take a look at what could be causing the issue. And after seeing a couple vids /post. I decided to do a basic troubleshoot so I started off with making sure the camshaft sensor was connected tight and BINGO it’s wasn’t lose to point where it would have just fallen off but it had a small play to it. Pushed it back in and turned the car on and it’s gone. Just came back from a bit of hard running and everything seems to be okay. I will def keep and eye out the next couple of days to see if it returns or not but I’ll keep you’ll posted man! Good luck to you as well!

Thank you, sir! I check this out after I get to work. I told the garage that it wasn’t necessary to remove the intake manifold to do a tune up, but they remained stubborn. I’ll bet this is a precise consequence of that action!

 

[Paladin611]

So, I instead stopped at the garage before going to work. It turns out that my camshaft sensors are not the problem, rather, a cylinder 5 misfire. I ordered a new coil pack to install on Friday. We’ll see how this goes. I definitely encourage the narrative that I have been observing here that when replacing the plugs on these cars, its advised to replace all of the coils as well. That makes two bad coils now. Only 52k on the car.

 

[Paladin611]

So after being out all day I finally got home to take a look at what could be causing the issue. And after seeing a couple vids /post. I decided to do a basic troubleshoot so I started off with making sure the camshaft sensor was connected tight and BINGO it’s wasn’t lose to point where it would have just fallen off but it had a small play to it. Pushed it back in and turned the car on and it’s gone. Just came back from a bit of hard running and everything seems to be okay. I will def keep and eye out the next couple of days to see if it returns or not but I’ll keep you’ll posted man! Good luck to you as well!

 

[Paladin611]

Did the issue return after adjusting the camshaft sensors?

 

[Paladin611]

Ok- now I have a 2nd brand new coil installed on cylinder 5. I’ll be testing this out in the morning when I’ll be on the expressway. Hopefully, I won’t experience anymore misfires. If I do- I’ll be buying four new coils so they will all be replaced. If I get a misfire after that…I’m gonna flip! Fingers crossed!

 

[Oso7]

Did the issue return after adjusting the camshaft sensors?

Nope, everything has been normal ever since !! Only thing that worries me is how the sensor got loose to began with. Only thing I can think of is maybe a cat tried getting itself some where to sleep lol as they’re many hanging out around my neighborhood. But other than that not to sure also hopefully everything turns out good brotha !

 

[Paladin611]

Nope, everything has been normal ever since !! Only thing that worries me is how the sensor got loose to began with. Only thing I can think of is maybe a cat tried getting itself some where to sleep lol as they’re many hanging out around my neighborhood. But other than that not to sure also hopefully everything turns out good brotha !

Lol- I’m glad everything turned out okay for you. Same here. Turned out that, in addition to the other work I had done, replacing the cylinder 5 ignition coil was the answer. All new plugs, and two coils. Problem solved.