Dreded P304 Misfire code

[Regs120]

Reverted back to stock and everything is back to normal. Only 15k miles with it Denso's with .22 gap (can't remember). I imagine it has something to do with the heatwave but didn't have this issue last summer in NJ.

Way too early to be having spark plug issues with this! About 1/2 through a tank of 93 octane from BP.

Scared me enough to rip the damn thing out and now thinking about selling it.

Even with the JB4 removed, CEL gone, and it running smoothly, do you think I need to replace the spark plugs?

 

[Terry@BMS]

Honestly 15k is about the range when the plugs start to wear. Some get 20-30k miles some less than 15k. Depends on the fuel used and driving habits. But email us your address we can send you an updated 2580 that may correct your issue.

 

[Regs120]

emailed burgersupport.

Have you seen this numerous times Terry ? Odd that it is starting now after a year worth of use.

 

[Terry@BMS]

Sure plugs wear out, electrical system can't jump the gap, misfires and stuttering pops up. Have you pulled a couple of the easy to reach plugs to check the condition?

On the 2580 the new firmware just gives us more flexibility to control certain things via the JB4 firmware rather than "hard coded" as it was before.

 

[Regs120]

Code mentioned cylinder 4. Is that outside the manifold ? What do you mean flexibility? What does this software do? Lax the safety features? If that is the case, does that only mean potentially damaging the car or is it just being overzealous because it detects something different in the car?

Is there a huge difference between the HKS vs Densos? The price difference is a bit steep - but obviously if they last longer and safer I would get the HKSs.

 

[Spaceme17]

To me the easiest thing to do is pull your plugs and check the gap. If it is too big or you can see wear on the electrodes, its simple enough to replace them.

And honestly, $60 even if its every 15K miles, is not a bad cost for the increased performance of the JB4.

 

[Regs120]

I am just going to have a local shop do them for 120 bucks. By the time I buy the tools and aggravation of maybe removing the manifold its worth it. I now know for me to run my car like this I am going to have to accept that the plugs will blow out every year or two. Not exactly thrilling but it's the price we have to pay for performance/sports cars.

I guess I could get the backend flash but then that will defeat the purpose of a piggy back and might as well go full tork tune since it will void the warranty for sure.

TBH I am a little turned off by the whole mod scene now with this car. The market sucks for it and ECU is a PITA to crack. Spark plugs is one thing, but then what? Coils and fuel injectors? Gaskets? Ugh.

 

[Terry@BMS]

Not sure why people think flashing is a solution to the factory plug/coil issues on the platform. I've not come across a flashed customer who hasn't done plugs if not before the flash very shortly after. The same weakness exists. Sure you can tweak dwell time a bit to force more current through the coils with a flash table change but then you run the risk of burning out coils from the higher current which are more expensive than plugs. A good condition plug with a small gap is the best solution to our weak ignition problem IMHO.

I've seen some guys running non-OEM coil kits but not followed up with them for long term feedback.

 

[Terry@BMS]

Code mentioned cylinder 4. Is that outside the manifold ? What do you mean flexibility? What does this software do? Lax the safety features? If that is the case, does that only mean potentially damaging the car or is it just being overzealous because it detects something different in the car?

Is there a huge difference between the HKS vs Densos? The price difference is a bit steep - but obviously if they last longer and safer I would get the HKSs.

The safety is on the JB4 side so the risk is potentially damaging the JB4 board when the coil fails to fire and unleashes an electrical torrent through the factory electrical system. So far not blown out any JB4 boards though relaxing up or even disabling it's safety.

 

[Regs120]

Not sure why people think flashing is a solution to the factory plug/coil issues on the platform. I've not come across a flashed customer who hasn't done plugs if not before the flash very shortly after. The same weakness exists. Sure you can tweak dwell time a bit to force more current through the coils with a flash table change but then you run the risk of burning out coils from the higher current which are more expensive than plugs. A good condition plug with a small gap is the best solution to our weak ignition problem IMHO.

I've seen some guys running non-OEM coil kits but not followed up with them for long term feedback.

Alright - just trying to wrap my head around this. As a casual car guy, its starting to become hard to justify modding this car. With my turbo 4 mustang, it was a one shot deal flash and didn't have to worry about ignition issues and didn't have to worry about increasing the maintenance intervals. The tune was offered by Ford Performance which was warrantied for three years. It was a mild tune, but it changed the performance of the car by a good noticeable margin.

The Stinger on the other hand seems to come with a slew of issues ranging from regular spark plug replacement, coil packs, and fuel delivery systems. I really was not anticipating changing the spark plugs this soon and a little disappointed. It's not the jB4's fault by any means it just the limitation of the car. I am not a mechanic, but using my common sense, if I am putting that much more stress on the system, what else will inevitable fail on me in the future prematurely? I think members here need to be a little more notified and consumer-aware that there isn't a good "casual" solution for modding this car.

 

[Terry@BMS]

The platform is what it is. I think you just need to accept 15k miles is a normal spark plug change interval for the platform. If you try some more expensive HKS plugs maybe they will make it to 20k miles for you?

 

[Regs120]

I talked to a fellow member with the same issue and said the updated
chip and new spark plugs helped him. So hopefully in a few weeks Ill be back on my 420 bhp feet. Thank you Terry.

 

[Terry@BMS]

Curious to see if it makes any difference for you.

 

[Flaniganskywalker]

I also wanted a tune--but was thinking of a permanent one from pressertech.A mild ECU I thought just optimized things better.I do not need another 90 hp--I would rather have half that and not worry about plugs and all the other things discussed.I mean with computers--isn't there a way to know what the limit of a mild tune is that can keep the warranty and maintenence normal.Also--and I am not doubting anyone--do you know if you are getting 420 out of that tune.I live near both pressertech and a dyno--I do not want to pay $1200 and find out the car only gained 10hp--and at the other end--I also do not want a tune that is aggressive enough to chew through sparkplugs or nix the warranty.I might just stick with an exhaust and nice intake so I can sleep well at night and not worry about reliability.I had a very rare type R crosstour--Honda had an exhaust and mildly tuned the ECU and the HP was listed at 310--which was almost a 40 HP gain over a normal crosstour and I had the car 10 years and it was never once in the shop.It was also a NA engine and they got 40 hp out of it and maintained the reliability.That is what I am looking for.I also have both the Type R Crosstour and Stinger on you tube--showing the exhaust on the Stinger.My you tube channel is under the name Flaniganskywalker--I wish KIA would support the mod scene a little more with this car.I am sure they could get 40 more reliable HP out of a TT V6 with some type of factory ECU tune.

 

[Regs120]

To clarify, you are going to risk voiding you warranty no matter how mild your tune is. If you tamper with the ECU they might find out.

For a mild but pretty recognized ECU bench tune
your best bet is Presser Tech imo. They a very professional outfit and very reputable with a lot of domestic and foreign cars. If I had an extra grand I would ship it without blinking. They also laugh at the fact you have to change spark plugs for these tunes, but theirs are not breaking any records. There is just not as many people with presser-tech to get a good idea of the performance or spark plugs issues compared to JB4 but you can check out the 1/4 mile thread in the drag forum.

 

[Flaniganskywalker]

I just want a little more pep.I will visit pressertech--the money is no problem--i just do not want reliability problems.The most tuned car i ever had was a stage 2 eclipse--a 2008.It was in the shop at least every 2 to 3 months for issues--fuel rails--sensors--misfires.When it ran it was fantastic--but I literally would almost flinch when I started the car--wondering if the check engine light would pop up--cut power and another trip to the dealer.honda got 40 HP out of my Crosstour and all it had was an ECU tune and exhaust--on the computer box was an R--tune--then again honda did it.They even got this on stock plugs and it kept the warranty>But mitsubishi did my eclipse.The stinger is prob in the middle of these 2 companies.I have learned one thing--you start getting problems with mods like this--it usually keeps going.I have seen some of the videos but definite answers are hard to come by.I have 2 guys on this forum that had pressertech--have had no problems--they seem honest and claim the car is faster--but neither had a dyno to see what the gains were.My Cosrstour also had a bigger oil cooler and bigger tranny cooler--it also had the euro spec Type R rotors and cross drilled discs--but those mods really did not add any power.

 

[Regs120]

Bench tunes normally have better "butt dynos" cause they can change more characteristics then just raw power. If done right they shift a lot smoother and your accelerator is more responsive. The only downside and it is big - if the pressertech tune goes to hell for you - consider the down time of shipping the ECU back - and then trying to get warranty work done and hoping they don't check. luckily all I had to do with the jb4 was turn it off and remove it. Nothing is full proof and although they are reputable the Kia stinger is a relatively new platform for them. So take it for what it is . My confidence in modding this car without issues is a bit shot right now and I think leaving it stock might just be the best bet. Changing spark plugs every 15k is not exactly casual daily driving to me.

 

[Flaniganskywalker]

Bench tunes normally have better "butt dynos" cause they can change more characteristics then just raw power. If done right they shift a lot smoother and your accelerator is more responsive. The only downside and it is big - if the pressertech tune goes to hell for you - consider the down time of shipping the ECU back - and then trying to get warranty work done and hoping they don't check. luckily all I had to do with the jb4 was turn it off and remove it. Nothing is full proof and although they are reputable the Kia stinger is a relatively new platform for them. So take it for what it is . My confidence in modding this car without issues is a bit shot right now and I think leaving it stock might just be the best bet. Changing spark plugs every 15k is not exactly casual daily driving to me.

I literally live down the street from pressertech.I am going to have a detailed talk with them about this.I have no problem with price--I have a huge problem with basic honesty on these--which is all over the place.I will also talk to KIA via email and see what they say--then print the email out if it contradicts anything and see which one can back anything with facts.I am like you and have had 50/50 with mods.one mod--honda--40 HP--no problems ever--Mitsubishi--maybe 60 to 80--and had all sorts of problems--even though they covered it--I got tired of taking it to the shop for 2 to 5 days at a time every couple of months.The lamda 2 engine is reliable and sturdy and its internals are well built--just want that balance..I have no prob with a mild 40 HP gain--which is within reason to not have reliability--fingers crossed.

 

[Flaniganskywalker]

I literally live down the street from pressertech.I am going to have a detailed talk with them about this.I have no problem with price--I have a huge problem with basic honesty on these--which is all over the place.I will also talk to KIA via email and see what they say--then print the email out if it contradicts anything and see which one can back anything with facts.I am like you and have had 50/50 with mods.one mod--honda--40 HP--no problems ever--Mitsubishi--maybe 60 to 80--and had all sorts of problems--even though they covered it--I got tired of taking it to the shop for 2 to 5 days at a time every couple of months.The lamda 2 engine is reliable and sturdy and its internals are well built--just want that balance..I have no prob with a mild 40 HP gain--which is within reason to not have reliability--fingers crossed.

Pressertech still does not do any local work due to covid--but he said it might be lifted soon.

 

[jsrob905]

I'm new to tunning but spark plugs take 45 min and it's always fun to spend a little time under the hood in exchange for a big boost in power. Changing plugs once a year is worth it to me to be able to return my car to stock in 5 min.