Can spark plugs cause misfire only under load?

[JSolo]

Did they say why the coil/boot failed?

 

[cncBilly]

Did they say why the coil/boot failed?

My guess would be…he launches a lot on stock plugs that are likely unevenly gapped. Just going by the fact he uses a Kia tech for a machanic.

 

[D.J.]

My guess would be…he launches a lot on stock plugs that are likely unevenly gapped. Just going by the fact he uses a Kia tech for a machanic.

And that is "hard" on coils???

 

[MerlintheMad]

Did they say why the coil/boot failed?

They did not. The service advisor said that they fail rarely and anytime. A hundred bucks a pop when it happens isn't exactly going to break the bank.

 

[JSolo]

My understanding (and someone can correct if im wrong). An ignition coil is nothing more than a transformer of sorts. There may be some electronics on the primary side (low voltage side). Maybe the bad plug caused a higher resistance to the coil which meant greater load on it. Resulting in greater wear - meaning not able to produce a good spark under load or heavy load.

I don't believe there's a maintenance interval for ign coils, but they do wear out/go bad over time.

 

[cncBilly]

And that is "hard" on coils???

I have no idea. But if you’re flooring it with a cracked plug I doubt the coil is happy.

 

[MerlintheMad]

My understanding (and someone can correct if im wrong). An ignition coil is nothing more than a transformer of sorts. There may be some electronics on the primary side (low voltage side). Maybe the bad plug caused a higher resistance to the coil which meant greater load on it. Resulting in greater wear - meaning not able to produce a good spark under load or heavy load.

I don't believe there's a maintenance interval for ign coils, but they do wear out/go bad over time.

My theory, backed up by this experience, is essentially what you said. I opined that one bad plug out of the batch of replacements late last September damaged the coil pack, which ruined the replacement-replacement plug in January: that plug behaved far worse than the "chugging" plug starting in October. But just as possible as a faulty sparkplug, is a failing coil pack first, destroying the new plug: or possibly this was already happening (in the beginning stages) with my OEM plugs and I just hadn't experienced "chugging" yet, but the car was down on power yet still smooth-running until the spark plugs change disturbed that: I had remarked quite some time ago, how my butt dyno was now used to the acceleration, but possibly a slow and steady failure of the number six cylinder coil pack was going on. "Chicken and egg" situation, coil pack or plug failed first?

(There was a bit of both, butt dyno and lowered power, going on here: because yesterday I had no trouble handling the resumed full power of what feels like a brand new car: and before, in the beginning, it took me a good year and a half to get to the point where I felt comfortable/confident in hitting the kickdown switch/WOT.)

 

[JSolo]

^^He said opined!!

tl;dr One should floor/wot their car periodically to check for issues.

I've yet to do that. Just don't drive like that and no where around here to do so safely.

I remember years ago I had great difficulty starting my motorcycle when hot. No issues when cold, or after sitting a while, but shut it off, run into the store, get back, crank crank crank... and more cranking.

When I did the tune up on it, plug gap was nearly double what the spec called for. It started fine - hot and cold, after installing new plugs. That's the extent of my ignition system issues. Never experienced a failed coil or plug on a car (yet).

 

[MerlintheMad]

Never experienced a failed coil or plug on a car (yet).

Neither had I, that I recall, until this past six months.

 

[JSolo]

^^I take that back!! I did experience ign failure in a car.

I was in my 4th gen camaro z28 6mt in a construction zone express lane with barricades on both sides. Car stalled out at 80 mph. Quick thought pushed the clutch down and coasted to an area I could pull over. The optispark failed.

LT1howto.com :: What is an Optispark and why do they fail?

 

[MerlintheMad]

The optispark failed.

WTH is that?

 

[CoconutRob]

Found this site. Haven't ordered yet but good price for coil packs plugs ect.

 

[CoconutRob]

Welcome sparekorea.com

 

[CoconutRob]

Left 273103L030
Right 27310-3L000

 

[MerlintheMad]

That's quite a savings from $100 apiece! Dealer markup?

 

[stevengraham]

Bumping this thread. Just bought a Kia Stinger GT1 2 months ago, with 39k miles on it now, and after some spirited driving in the LA Canyons(launched it once) im now having misfires.
First got a P0306 code (Cylinder 6) and took it in to the Kia dealership to have the spark replaced. 2 weeks later they replaced the spark plugs in cylinders 1,2, 4, 5, and 6 under warranty.
Car was running fine for three days until coming back home, I was on sport mode and pushed the throttle, noticed chugging and quick engine light. Took it to OReillys and got a P0304.
Knowing what I know now from reading this forum I will be taking it back to Kia tomorrow and seeing if they will do a proper job and replace the coil packs and plugs.

Sorry for the long spiel.

 

[ChaneRZ]

Change the coil packs. If you’re having codes when under wot, maybe you need to gap your plugs. Factory gap is so wide for the Stinger.

 

[DoctorStiches]

Bumping this thread. Just bought a Kia Stinger GT1 2 months ago, with 39k miles on it now, and after some spirited driving in the LA Canyons(launched it once) im now having misfires.
First got a P0306 code (Cylinder 6) and took it in to the Kia dealership to have the spark replaced. 2 weeks later they replaced the spark plugs in cylinders 1,2, 4, 5, and 6 under warranty.
Car was running fine for three days until coming back home, I was on sport mode and pushed the throttle, noticed chugging and quick engine light. Took it to OReillys and got a P0304.
Knowing what I know now from reading this forum I will be taking it back to Kia tomorrow and seeing if they will do a proper job and replace the coil packs and plugs.

Sorry for the long spiel.

My code was cylinder 6 as well dont spend money on coil packs untill you upgrade to hks plugs gapped .028 that is what i run and since changing plugs no missfire. Also i only use good fuel no stop n shop or costco fuel , arco, sinclair ect

 

[MerlintheMad]

My code was cylinder 6 as well dont spend money on coil packs untill you upgrade to hks plugs gapped .028 that is what i run and since changing plugs no missfire. Also i only use good fuel no stop n shop or costco fuel , arco, sinclair ect

Costco is good gasoline. You don't recommend a "good fuel", just diss several not good ones (in your opinion).

Replacing No. Six cylinder coil pack fixed my sparkplug problem, which was that the fouled coil pack was ruining each replacement plug in c. two weeks: it wouldn't matter what the gap is.

 

[DoctorStiches]

I dont mean to have a reoccurring beef with you merlin. I was only posting.
Forgive me!

Costco is good gasoline. You don't recommend a "good fuel", just diss several not good ones (in your opinion).

Replacing No. Six cylinder coil pack fixed my sparkplug problem, which was that the fouled coil pack was ruining each replacement plug in c. two weeks: it wouldn't matter what the gap is.