3.3TT Cylinder #6 Misfire

[ecko04]

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

Make sure you get enough drive cycles on it to rule out any pending codes. Sometimes codes won’t set unless the event has been sustained for a few drive cycles. Make sure you’re turning off the car to complete/start a drive cycle. Just driving around nonstop doesn’t do the trick. Otherwise you appear to be in the clear.

 

[ScottyDangles]

Alright moving on!

Make sure you get enough drive cycles on it to rule out any pending codes. Sometimes codes won’t set unless the event has been sustained for a few drive cycles. Make sure you’re turning off the car to complete/start a drive cycle. Just driving around nonstop doesn’t do the trick. Otherwise you appear to be in the clear.

Proud to say no engine light. I think these were stored codes that came up. I ended up going through the Kia Service manual and re-torquing all my bolts to the proper specifications since I did the job hastily since it was 30 plus degrees out. Thanks again for the insight.

 

[ecko04]

Alright moving on!



Proud to say no engine light. I think these were stored codes that came up. I ended up going through the Kia Service manual and re-torquing all my bolts to the proper specifications since I did the job hastily since it was 30 plus degrees out. Thanks again for the insight.

Fantastic! Keep us posted!

 

[AC1981]

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

Hi all! I am coming into this conversation late, so I apologize. My 2019 GT2 is currently at the dealership for its SECOND MISFIRE! They apparently fixed and replaced the first plug three weeks ago, then yesterday my MIL light came on again and the car started “stuttering” like before. I told them yesterday that I want all of the spark plugs and coils replaced because this is a known problem and they said that it doesn’t work that way. That they have to do what Kia tells them to do.

I nor my husband are car savvy, we have to pay to have people fix this stuff.... please oh Stinger Forum Gurus help me figure out what I need to do to get my baby running like it was.

Thank you!!!

Ps. I do not race my car...i drive it to work.

 

[Revvdmedia]

Hi all! I am coming into this conversation late, so I apologize. My 2019 GT2 is currently at the dealership for its SECOND MISFIRE! They apparently fixed and replaced the first plug three weeks ago, then yesterday my MIL light came on again and the car started “stuttering” like before. I told them yesterday that I want all of the spark plugs and coils replaced because this is a known problem and they said that it doesn’t work that way. That they have to do what Kia tells them to do.

I nor my husband are car savvy, we have to pay to have people fix this stuff.... please oh Stinger Forum Gurus help me figure out what I need to do to get my baby running like it was.

Thank you!!!

Ps. I do not race my car...i drive it to work.

I assume you are completely stock and not modified? If yes, if they've already replaced the plug in that particular cylinder and it is still misfiring, they should be changing the coil for the order of operations. If the dealer does not follow what Kia recommends, it can come out of their pocket. A really good dealer may do this, many will not, they don't want to risk extraneous expense.

 

[AC1981]

I assume you are completely stock and not modified? If yes, if they've already replaced the plug in that particular cylinder and it is still misfiring, they should be changing the coil for the order of operations. If the dealer does not follow what Kia recommends, it can come out of their pocket. A really good dealer may do this, many will not, they don't want to risk extraneous expense.

I am stock other than an upgraded exhaust which Kia installed. Just heard from them and they said they are replacing a spark plug behind the coil which they will have to wait for the part. Asked them if it was the same plug... the we’re going to call us back. I will ask why they are not replacing the cool as well. Very frustrating.

 

[Revvdmedia]

I am stock other than an upgraded exhaust which Kia installed. Just heard from them and they said they are replacing a spark plug behind the coil which they will have to wait for the part. Asked them if it was the same plug... the we’re going to call us back. I will ask why they are not replacing the cool as well. Very frustrating.

Unfortunately that might be their standard order of repair. Kia might "require" 2 failed plugs before they replace the coil. If you have this issue again following a plug replacement and on the third repair they don't look into the coil, they need to rethink their strategy. Another question is what octane are you running? There are users with tunes that mildly question if pre-ignition (low octane fuel causes this) might be the reason for blown plugs. Are you running 87 octane, or 91+?

 

[Hydrajin]

I am stock other than an upgraded exhaust which Kia installed. Just heard from them and they said they are replacing a spark plug behind the coil which they will have to wait for the part. Asked them if it was the same plug... the we’re going to call us back. I will ask why they are not replacing the cool as well. Very frustrating.

They replaced mine and as I drove off the lot I blew the same plug under somewhat hard acceleration (shift at 4krpm). Mine has borla exhaust and injen intake, pretty much stock car.

I recommend buying the ikh24s or ikh27s made by denso (about $12 each plug) and having them install them across all cylinders. My crappy dealers here replaced the first plug at their own cost and charged me for a second plug. Dealer sells plugs for about $50 to $60 per plug where I live, and $225 for the install of 1 plug. If you have a local chapter on the forum, check if anyone locally has done their plugs and is willing to help out installing them for you, or just go to dealer service or any decent shop with the densos and have them install them.

1 thing to remember is have then gap the plugs to about .024... This is a critical step for any forced induction engine, if the gap is big on a plug, it will not fire.

 

[Hydrajin]

I am stock other than an upgraded exhaust which Kia installed. Just heard from them and they said they are replacing a spark plug behind the coil which they will have to wait for the part. Asked them if it was the same plug... the we’re going to call us back. I will ask why they are not replacing the cool as well. Very frustrating.

Every plug is under a coil, they won't replace a coil because a coil is a $400-600 part usually, and it will in most cases outlive every other component of an engine because it is solid state, they're filled with a resin or epoxy of some form to hold the internals together as 1 solid chunk. Not much can really go wrong in a coil unless it was defective to start with or the connection become loose with age (many many years of service).

 

[AC1981]

Unfortunately that might be their standard order of repair. Kia might "require" 2 failed plugs before they replace the coil. If you have this issue again following a plug replacement and on the third repair they don't look into the coil, they need to rethink their strategy. Another question is what octane are you running? There are users with tunes that mildly question if pre-ignition (low octane fuel causes this) might be the reason for blown plugs. Are you running 87 octane, or 91+?

That is a great question... when I fill it is always 91+, but I do not know what my husband has been doing. Thank you for your responses. Have a great day!

 

[AC1981]

Every plug is under a coil, they won't replace a coil because a coil is a $400-600 part usually, and it will in most cases outlive every other component of an engine because it is solid state, they're filled with a resin or epoxy of some form to hold the internals together as 1 solid chunk. Not much can really go wrong in a coil unless it was defective to start with or the connection become loose with age (many many years of service).

Got it. So it’s more about the quality of the plug and correct gapping.

 

[Hydrajin]

That is a great question... when I fill it is always 91+, but I do not know what my husband has been doing. Thank you for your responses. Have a great day!

Fuel type shouldn't really matter in modes other than sport mode which has higher pressure running through the engine. The computer should detect knock (so should your ears, would sound like a deisel at some point with metallic knocking that's muffled) and adjust timing as a counter measure to prevent damage.

 

[Hydrajin]

Got it. So it’s more about the quality of the plug and correct gapping.

Any brand name (ngk, denso, bosch, etc..) plug will have equal quality, it's the heat range of the plug, the plugs ability to get rid of heat to prevent expansion and damage to itself. I personally put the denso ikh27s because I know there is running in my future, denso ikh24s will do fine on a stock car but a member here had heat related failure when chip boosting on the 24s which may mean they are not suitable for extra boost, or it could be just that motor running a little hotter overall due to external causes which raised the plug heat above it's design and cracked it.

You can find hks plug or denso plug part numbers on the forum for the denso ikh24 and the ikh27, much cheaper than OEM and superior. I'm not sure if anyone has yet to find a Bosch or NGK higher heat than oem that will fit.

 

[Brian B]

Denso (5346) IKH24
I just lost two of these plugs recently with the P0300 misfire code,

I do i lot of drag racing but mostly keep these at map 2 almost never venturing into map 3 or higher.

 

[Brian B]

Denso (5346) IKH24
I just lost two of these plugs recently with the P0300 misfire code,

I do i lot of drag racing but mostly keep these at map 2 almost never venturing into map 3 or higher.

Daily driving was always on map 2 or 1.
Lasted about 5 months 6000k miles before failure.. not good.

 

[Tonkabob]

Fuel type shouldn't really matter in modes other than sport mode which has higher pressure running through the engine. The computer should detect knock (so should your ears, would sound like a deisel at some point with metallic knocking that's muffled) and adjust timing as a counter measure to prevent damage.

Sport and Comfort both hit full boost. Only difference is faster shifting and holding higher RPMs in Sport. Comfort more likely to knock lugging a low gear with high boost. But true these cars don't really knock as it will adjust before you would notice.

 

[Hydrajin]

Sport and Comfort both hit full boost. Only difference is faster shifting and holding higher RPMs in Sport. Comfort more likely to knock lugging a low gear with high boost. But true these cars don't really knock as it will adjust before you would notice.

That's what the torque app boost gauge was telling me too but when I installed the hks bovs, eco venting is almost an eagle like whistling sound, comfort is a little sharper like high pressure whistle, and sport mode is a very sharp whistle that sounds like a higher, and more instant, pressure release. I trust boost gauges all day long but when a mechanical indicator such as a blow off valve releasing pressure sounds like a higher pressure dump comes along, I'll take that as the more accurate indicator of pressure.

 

[jadabish11]

FWIW...my JB4 tuned Genesis G80 3.3t (w/ 70k miles) has been a focus project of mine these last two months. Here are 2 separate logs days apart of wide open pulls I've done 2nd-4th & JB4 increasing boost (+AFR)...the first with OEM Spark Plugs. The second with Denso 1-step plugs ordered from KDM Warehouse.

Do with this information what you may.

 

[jadabish11]

Basically, there's slightly less timing advance w the denso plugs over what was (apparently) OEM in there (bought from Carvana at 35k mi). Asked the shop to gap to .022 but they had already been kinda janky on me so I legit am waiting on the mech to get back from vacation so we can confirm he gapped em. Idk, I'm not sold that they did. Better safe than sorry, but still....the logs show a decent improvement over OEM. When I really saw benefit to spark was after adding BOVs (?) + 30min battery disconnect to my setup .

 

[LeeChewie70]

Hey Guys -

Does anyone know which cylinder is cylinder #6? I have a misfire under load and think I might have a bad spark plug. I just want to go in and change it rather than take it to the dealer.

In case this is important I have the BMS JB4 with Denso plugs gapped at .025. I know terry recommends .022, he has also confirmed .025 should not be an issue.

Thanks,
Scott

Might be #6 coil pack is bad. Might check if there is timing correction for the possible bad coil pack. I had two go out and the power loss was random.