3.3TT Cylinder #6 Misfire

[ScottyDangles]

I run Map 5 almost exclusively after reviewing logs and having access to E85. I run the HKS plugs, I know — an unpopular opinion given their price, but I’ve had no spark plug issues.

Hold your head high! You bought the better spark plug and the right one the first time, you spent no more than any of us who bought the IKH24s!!

I'd be curious to hear if Terry has had any issues with the IKH24s...

 

[StungBlueGT2]

Hold your head high! You bought the better spark plug and the right one the first time, you spent no more than any of us who bought the IKH24s!!

I'd be curious to hear if Terry has had any issues with the IKH24s...

Yes he bought the better plugs, but he easily spent 3 times the amount of money for the HKS’s(~$150) instead of the Densos(~$50). And since those are colder plugs that are intended for consistently running higher boost they likely won’t last nearly as long as OEM change intervals. Those HKSs may need to be replaced every ~20k miles anyway so buying the Densos still probably cost much less in the long run.

It would be great to know why the limited few of you are having problems, but if BMS has sold several hundred, if not 1k’s of JB4s most of which bought Densos, it’s still a very rare occurrence. I’d bet the couple of you that had problems don’t race their Stingers at WOT & 18psi+ often and may have simply had carbon buildup on the plugs which led to problems. That effect would be much worse with colder plugs so the Ikh24s are still a better choice for 8/10 JB4 users.

Interesting note. The only reports of blown Densos are users from Canada, or much higher boost than map2 by using WMI. Seems more likely to be related to the poor Canadian fuels people keep complaining about, or over the 75-100hp rule of thumb for 1 step colder plugs.

 

[Hacksaw907]

Interesting note. The only reports of blown Densos are users from Canada, or much higher boost than map2 by using WMI. Seems more likely to be related to the poor Canadian fuels people keep complaining about, or over the 75-100hp rule of thumb for 1 step colder plugs.

That is an interesting observation, for sure. With what you said about carbon deposits, I wonder if anyone who has had an ikh24 blow on them still has it around to see if there was a lot of carbon build up. As for whether it might be caused by bad Canadian fuel/too high boost, I'd accept that, and in which case, just use a lower map.

I will admit that I knew nothing about cars up until I got this stinger, hence why I'm erring on the more cautious side of things with these plugs. Though perhaps I should consider the possibility that getting a chip/tune may not be for me haha...

 

[Revvdmedia]

Yes he bought the better plugs, but he easily spent 3 times the amount of money for the HKS’s(~$150) instead of the Densos(~$50). And since those are colder plugs that are intended for consistently running higher boost they likely won’t last nearly as long as OEM change intervals. Those HKSs may need to be replaced every ~20k miles anyway so buying the Densos still probably cost much less in the long run.

It would be great to know why the limited few of you are having problems, but if BMS has sold several hundred, if not 1k’s of JB4s most of which bought Densos, it’s still a very rare occurrence. I’d bet the couple of you that had problems don’t race their Stingers at WOT & 18psi+ often and may have simply had carbon buildup on the plugs which led to problems. That effect would be much worse with colder plugs so the Ikh24s are still a better choice for 8/10 JB4 users.

Interesting note. The only reports of blown Densos are users from Canada, or much higher boost than map2 by using WMI. Seems more likely to be related to the poor Canadian fuels people keep complaining about, or over the 75-100hp rule of thumb for 1 step colder plugs.

I was actually thinking that what might be the underlying cause of cracking plugs is knock. Since you mention Canadian fuel and many of us question the knock resistance of same level octane, if Canadians are seeing more knock on our cars (because of fuel) and if knock blows plugs...one can only assume...

 

[ScottyDangles]

Here's a picture of the spark plugs removed from my car. Any thoughts here? The one on the far right is the blown one, it was in Cylinder 5.

I do not race my Stinger and spend most of the time on my daily commute to work and on Map 1. I try do some WOT pulls when I get a chance, but traffic in the Greater Toronto Area is heavy, tough to do.

 

[Revvdmedia]

Here's a picture of the spark plugs removed from my car. Any thoughts here? The one on the far right is the blown one, it was in Cylinder 5.

I do not race my Stinger and spend most of the time on my daily commute to work and on Map 1. I try do some WOT pulls when I get a chance, but traffic in the Greater Toronto Area is heavy, tough to do.

One of these plugs is not like the other....notice how 3 have different porcelain (3 stripes vs none) and 3 have bronze colored tops and 3 are more like black. Where did you buy these from? Some have reported getting plugs from Amazon and whatnot and think they might be knock offs, not legitimate Densos. They could be revised plugs too but not sure.

 

[ScottyDangles]

One of these plugs is not like the other....notice how 3 have different porcelain (3 stripes vs none) and 3 have bronze colored tops and 3 are more like black. Where did you buy these from? Some have reported getting plugs from Amazon and whatnot and think they might be knock offs, not legitimate Densos. They could be revised plugs too but not sure.

Noticed that as well after removing them. I had the dealer do the install so I never noticed. I bought these off of BMS... probably just a revision. The IKH27s I got all look the same.

 

[turboAWD]

There have been several reports of different models of Densos being shipped, even within the same order, on here.. By that, I mean slightly different logos / labeling.

 

[ecko04]

Yes he bought the better plugs, but he easily spent 3 times the amount of money for the HKS’s(~$150) instead of the Densos(~$50). And since those are colder plugs that are intended for consistently running higher boost they likely won’t last nearly as long as OEM change intervals. Those HKSs may need to be replaced every ~20k miles anyway so buying the Densos still probably cost much less in the long run.

It would be great to know why the limited few of you are having problems, but if BMS has sold several hundred, if not 1k’s of JB4s most of which bought Densos, it’s still a very rare occurrence. I’d bet the couple of you that had problems don’t race their Stingers at WOT & 18psi+ often and may have simply had carbon buildup on the plugs which led to problems. That effect would be much worse with colder plugs so the Ikh24s are still a better choice for 8/10 JB4 users.

Interesting note. The only reports of blown Densos are users from Canada, or much higher boost than map2 by using WMI. Seems more likely to be related to the poor Canadian fuels people keep complaining about, or over the 75-100hp rule of thumb for 1 step colder plugs.

Yes, I paid more for the HKS plugs than I otherwise would for Denso plugs. You know what else I’m doing? NOT spending my time hunting down spark plug issues.

It has been erroneously stated over and over again that colder plugs will foul quicker. This may have been the case in 1990 but it’s simply not true in 2019. In fact, it’s preferred to have a plug foul due to it being colder than the alternative when it’s hotter, which is severe engine damage.

There has been absolutely no evidence to suggest that colder plugs in the Stinger will expedite the need to replace plugs. In fact, quite the opposite seems to be the case, where stock plugs are the ones fouling/cracking and in need of replacement sooner than the service interval would suggest and clearly some of the Denso plugs.

While someone may have spent $150 on HKS plugs, point me to the thread where someone using them has had their ceramic crack, plug fail or experienced a bad coil pack.



The sample size is smaller, for sure, but the failure rate at this point is nil.

I don’t know about you, but if it costs $150 to not swap Densos every other oil change — downtime and labor add up — sign me up for that any day of the week. I’d prefer to not have to hunt down which plug decided to opt out of functioning.

What anyone chooses to run is their decision; I was simply adding to the discussion that some of us are not using Denso plugs and we’re hard pressed to find links to failure with those. Maybe it’s the Canadian fuel, maybe it’s the plug, or maybe a combination.

 

[StungBlueGT2]

Yes, I paid more for the HKS plugs than I otherwise would for Denso plugs. You know what else I’m doing? NOT spending my time hunting down spark plug issues.

It has been erroneously stated over and over again that colder plugs will foul quicker. This may have been the case in 1990 but it’s simply not true in 2019. In fact, it’s preferred to have a plug foul due to it being colder than the alternative when it’s hotter, which is severe engine damage.

There has been absolutely no evidence to suggest that colder plugs will expedite the need to replace plugs. In fact, quite the opposite seems to be the case, where stock plugs are the ones fouling and in need of replacement sooner than the interval would suggest and clearly some of the Denso plugs.

While someone may have spent $150 on HKS plugs, point me to the thread where the certain has cracked, plug has failed or coil has gone bad for anyone running HKS plugs. The sample size is smaller for sure but the failure rate at this point is nil.

I don’t know about you but if it cost $150 to not swap Densos every other oil change — downtime and labor add up — sign me up for that any day of the week. I’d prefer to not have to hunt down which plug decided to opt out of functioning.

What anyone chooses to run is their decision; I was simply adding to the discussion that some of us are not using Denso plugs and we’re hard pressed to find links to failure with those. Maybe it’s the Canadian fuel, maybe it’s the plug or maybe a combination.

No need to be defensive. I’m not criticizing you or saying you made a bad choice. I’m simply starting the facts.

You and probably 99% of the 1000s of Denso users are not hunting down spark plug issues either. The couple of examples stated here doesn’t represent the rest of the users that are happy and having no problems with their plugs.

And not sure where you’re getting your info, but it’s documented and proven that colder plugs do not get as hot, and in turn do not burn off as much carbon deposits. Carbon deposit buildup usually causes detonation which is dangerous in itself and can cause more damage than just blown plugs.

I do partially agree that it’s generally better to have a fouled plug than a extremely hot plug that may malfunction. But that would only happen if your usually running significantly more boost than map2/3 and making more than 100hp over stock power levels. If that was the case than using 2step colder plugs would be fitting, however most JB4 users don’t use map5, 7 or 8 so that only applies to a very small percentage of users.

Again your assumptions are incorrect and it’s well known that running higher boost will wear down electrodes faster and in turn need plugs to be replaced more often. Higher performance plugs are also known for quicker replacement because they are generally causing more wear & tear due to running more power. Simple explanation here.
How Often Should Spark Plugs Be Replaced? | YourMechanic Advice

And stock plugs have had issues simply because of Kia’s poor gapping parameters. Almost everyone that had issues with stock plugs, including myself, found that it was due to unusually large & inconsistent gaps, some as a bad as .038”

Again, not arguing that HKS’s aren’t good plugs but I personally know someone that just got rid of his M45ILs because he was having serious misfires running the JB4. Even if there were ~1/100 JB4 HKS users with issues, that’s a much higher percentage of failure rate than the ~3/1000 of Densos with problems...

I doubt anybody is replacing Densos around 10k miles unless user error, bad gas or too much boost for step1 colder plugs. Also, Im pretty sure most people only running map1-3 would rather spend $50 to get 20k-30k miles out of Densos with a next to nothing chance of issues, than to spend $150 for HKSs that have a higher failure rate %, increased chances of fouling, and likely have to change them in less time.

I agree that whatever anyone wants to run is there decision, and everyone wants to defend their own choice. However your input, even if unintentional, gave the impression Denso users made a mistake with their choice.

Bottom line, both plugs are great and the facts show that issues are extremely limited and likely caused by other circumstances than just one plug being vastly superior to the other. Just saying, be happy with your choice and try not to make others feel that they made the wrong one when all the facts say otherwise.

 

[Angel]

I will share my experience. Not picking any sides of the colder plug debate.

I had 1 step colder plugs denso IKH24 for about 4-5 months with no issues. Ran the JB4 daily on map 2. I did on track day and ran map 5 on E30 mix. Never any issues. These were gapped .023-.024

Last month I installed WMI kit and when I tested the wmi kit I blew 2 plugs on Cylinder 3 and 6. Not sure why or what caused it but I got misfires and I have videos that I have shared on it when it happened.

I bought some Denso IKH27 which are 2 step colder. I installed those and gaped them at .024

I have not had any issues on the last month. I have used wmi on map 8 without any issues. I did 1 track event today and got an 11.7. All this was done on pump gas and 90 degree weather, all runs were on map 3 and map 5 since I could not get my wmi to work. I will be pulling my plugs next weekend to inspect. I have about 1000 miles on the new plugs. I was told by some on this forum that 2 step colder plugs would cause issues and foul early. I have not had any issues yet. Once I pull plugs and inspect I can add more valuable information to this thread. I did pull the plugs at like 500 miles and noticed no carbon build up or issues with the plugs.

 

[Gtecko]

this is an interesting thread

 

[Revvdmedia]

We will never know the true failure percentage because not all Stinger owners participate in this forum, not all members here will be vocal of their problems or successes, not all will admit to even being tuned due to fear losing their warranty, etc.

 

[Secondchance]

I don’t know you personally, but I’ll say this — during the brief time I’ve been a member of this forum, ~1 month, when I disagree with you about something you start your retort with either "take a chill pill, calm down, or no need to be defensive", when what you need to realize is just by conjuring those words you're being dismissive. You control what you say, not how someone else feels, which means you do not control how they respond — and suggesting how someone should respond will typically illicit a stronger response.



So you’re dismissing the SEVERAL owners here that have had issues with their Denso plugs? Nothing new here given how you are quick to dismiss people. If they’ve encountered issues it matter to them and they don’t have to be running Map 3 or higher to experience those issues.



You're referencing an article, not from a performance vendor or spark plug manufacturer but a general article from general mechanics, not engineers, from 4 years ago with no citations and no reference to manufacturer specifics; once again opinion.



Almost everyone? You know almost every Stinger owner? That’s surprising. Almost everyone is recall territory. Yes, the plugs were problematic, but to say almost everyone is absurd.



Are you making up numbers again? Certainly sounds like it. Need something to justify your narrative?



Dismissing the problems encountered by users again. Must be user error, can’t possibly be the Densos.

It's amazing that you can spout fiction out of thin air, like what "most JB4 owners run..." so easily. You don't know most JB4 owners and this information isn’t publicly available.

Just because they're not on this forum, or facebook, doesn't mean they aren't running maps 5 or higher. You can make a statement about what you believe most run but anything more than that is misleading.

HKS has a higher fail rate? Where’s your proof? Increased chance of fouling? Where’s your proof? Likely to have to change them in less time? Where’s your proof?

As per usual you don’t have any.

When running a colder spark plug fouling occurs when the plug tip doesn’t stay hot enough to burn off the carbon deposits, and so a build up occurs. If you're running more boost, even intermittently, then it would reason that these build up issues will not become a hindrance and therefore the plugs will not be fouled sooner — after all spark plugs are designed to clean themselves up to a certain point.

We have documented proof of several Denso plugs failing. If someone chooses to run them — that's fine, but they should be aware of other options, which was the purpose of my initial post. How you managed to extrapolate more from a two sentence post is beyond me.

At no point did I tell anyone to buy anything, just a statement of what i'm using and what my experience has been, which is 1 data point.

While I agree with almost everything you wrote here, it is worth mentioning that the comparison of a denso 5346 to the HKS plugs isn't the apples to apples comparison this topic deserves. If people were having a similar blow out issue on the Denso 5347 plugs, which compares more evenly with the HKS plugs. I myself have been running the 1 step colder 5346 densos without issue on map 2, but will likely look at the 5347 2 step colder plugs when I sway them out.

Unrelated to your post, I think its hilarious that Carbon build up is being discussed at all. Anyone changing these plugs out is likely running one of the tuning options out there, which means most if not all should be using a high quality 91/93/94 octane fuel. Carbon build up as a whole is significantly reduced using premium and ultra premium fuels, as they burn more efficiently, as well as typically have additives to promote reduction in carbon build up on top of the added benefit from the better fuel itself. Anyone who also argues the fact that running a denso/HKS plug will require changing the plugs out more frequently than the stock plugs which will add costs needs to realize that its their decision to tune the vehicle, which requires the plugs to be swapped for performance and safety reasons, that adds the costs and time associated with changing plugs out more frequently. Stop viewing it as a con associated with changing the spark plugs, and start viewing it for what it really is, being a potentially necessary expenditure caused ENTIRELY by ones choice to tune their stinger.

 

[ecko04]

@Gtecko @Revvdmedia @Secondchance I agree with everything you folks stated. I opted out of this thread for my own sanity.

 

[Revvdmedia]

There is one observation I would like to make regarding Hyundai and Kia and their spark plug choices. While I haven't gone into full research as to why, and it could simply be vendor selection, the 2.0L TGDI has undergone 2 spark plug revisions (it is on its third style of plug). When I was trying to find appropriate replacement plugs for my wife's 2.0 TGDI Santa Fe (it is completely stock and I wanted OEM plugs), I found that Hyundai had revised the plug choice twice, and a short look in the forums had people noting it was due to some level of performance issues with the plugs.

Long story short, I won't be surprised if the 3.3T sees revised plugs in not too long due to the issues that a few even stock cars are having with them. It would be interesting to see what the OEM engineers choose to replace the current plugs with, 1 step colder? Different brand?

 

[Hydrajin]

I haven't noticed any cold start issues living in one of the coldest capitals in the world lol. Yet to stress these in true winter temperatures but -5°C start was as normal as +40°c that we have been having lately. Winter where I am will really show if extreme cold start has any issues when we get -40°C and lower.
As for fouling, I have driven a good 5K km on the 27's I'll pull one out and inspect for white residue but I suspect if the stock and 24s are blowing due to heat, the 27 is unlikely to foul with heat high enough for it to self clean or compromise a hotter plug. No clue why Terry has the 24s rather than the 27s on the site but I know the very popular hks upgrade is 2 steps colder than stock just like the denso 27s.

Will report back when I get a chance to inspect a plug or 2; 5k km should be way more than enough for signs of fouling plugs if they are indeed too cold for the motor.

@ScottyDangles @Revvdmedia
Got a chance to pull out the coldest running plug today, the one with most ambient cooling and airflow over it's coil. Happy to report at +5000km later the plugs looks like they're self cleaning as they should and 2 steps colder seems to run perfectly fine on a stock car. All I have are intake and exhaust, no increased boost or any stress on the motor. Most of my driving is slow traffic or highway so engine rpms are pretty much always low and my daily commute is done on eco or comfort modes where boost levels peaking at ~9 psi as opposed to the ~12psi found in sport mode. Ikh27s or any ngk heatrange 9 will run reliably it seems, even on a stock engine.

 

[ScottyDangles]

@ScottyDangles @Revvdmedia
Got a chance to pull out the coldest running plug today, the one with most ambient cooling and airflow over it's coil. Happy to report at +5000km later the plugs looks like they're self cleaning as they should and 2 steps colder seems to run perfectly fine on a stock car. All I have are intake and exhaust, no increased boost or any stress on the motor. Most of my driving is slow traffic or highway so engine rpms are pretty much always low and my daily commute is done on eco or comfort modes where boost levels peaking at ~9 psi as opposed to the ~12psi found in sport mode. Ikh27s or any ngk heatrange 9 will run reliably it seems, even on a stock engine.

Very nice!

So far things seem to be going well with my change over to the IKH27s. Idle is smooth, power is strong.

I did get a check engine light yesterday which put the car into limp mode, which scared me. I got the following codes, P0306 (Cylinder 6 misfire), P0400 (EGR related) and P0000 (limp mode). I reset it yesterday and has yet to come back. Not sure what to think, car is running fine otherwise and ran fine leading up to the engine light coming on...

 

[Hydrajin]

Very nice!

So far things seem to be going well with my change over to the IKH27s. Idle is smooth, power is strong.

I did get a check engine light yesterday which put the car into limp mode, which scared me. I got the following codes, P0306 (Cylinder 6 misfire), P0400 (EGR related) and P0000 (limp mode). I reset it yesterday and has yet to come back. Not sure what to think, car is running fine otherwise and ran fine leading up to the engine light coming on...

Could be a false code, keep fingers crossed coil insulator boot hasn't been shot, mine had minor marks along where the blown plug was shorting to engine block.

 

[ScottyDangles]

Well its been two days now and no codes, car runs and sounds fine, fingers remain crossed! Thanks again for the insight and help!