Misfire investigation (in part)

[Maximus Gladius]

21 JTR, second engine, 50k kms.
Had the code PO305. Misfire in cylinder 5 but didn’t store the code and was told to monitor it.

The first sign I thought something wasn’t quite right before it misfired was some engine fluttering at 6500RPM, full throttle going up an incline. First thought I had was maybe spark plugs?? Then after some time the fluttering caused a flashing engine light and engine vibration and a P0305 code. Engine light self healed and engine runs great and nice and quiet.

I figured today I’d pull the #5 coil and plug and this is the plug. It smells like oil but it isn’t wet. I had a new plug to replace it with. Any thoughts as to the condition of the plug?

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[Gvsukids]

21 JTR, second engine, 50k kms.
Had the code PO305. Misfire in cylinder 5 but didn’t store the code and was told to monitor it.

The first sign I thought something wasn’t quite right before it misfired was some engine fluttering at 6500RPM, full throttle going up an incline. First thought I had was maybe spark plugs?? Then after some time the fluttering caused a flashing engine light and engine vibration and a P0305 code. Engine light self healed and engine runs great and nice and quiet.

I figured today I’d pull the #5 coil and plug and this is the plug. It smells like oil but it isn’t wet. I had a new plug to replace it with. Any thoughts as to the condition of the plug?

Engine tick?

 

[ShadowsPapa]

21 JTR, second engine, 50k kms.
Had the code PO305. Misfire in cylinder 5 but didn’t store the code and was told to monitor it.

The first sign I thought something wasn’t quite right before it misfired was some engine fluttering at 6500RPM, full throttle going up an incline. First thought I had was maybe spark plugs?? Then after some time the fluttering caused a flashing engine light and engine vibration and a P0305 code. Engine light self healed and engine runs great and nice and quiet.

I figured today I’d pull the #5 coil and plug and this is the plug. It smells like oil but it isn’t wet. I had a new plug to replace it with. Any thoughts as to the condition of the plug?

You took it all the way to redline, full throttle?
6500 is redline.

I'm not so concerned about 'smells like oil' as I am - that plug looks like crap.
It's really nasty and I'd never put a plug that looks like that back in. In fact, I'd suggest it needed replacement a few thousand miles ago. Look at that center electrode and the surfaces of the plug.

I'd not be surprised if that plug was your misfire - but I also wonder about the appearance of it in general.
That plug looks horrible for only 50,000 km (30,000 miles)
It looks more like 80,000 - 100,000 miles to me.
I've got over that sort of mileage on my 4.0 and they are just starting to show wear.
Also that's a weird pattern in the carbon, like it's burned on, hardened and pitted.
The oil smell could be a clue - but taking it to that RPM isn't ideal, either.

Do you typically wind it up to redline?

 

[Lunentucker]

It looks like it's been burning water.

 

[ShadowsPapa]

It looks like it's been burning water.

I had wondered about that but coolant in the chamber results in a white substance on the plug due to the chemicals left behind.

The pattern on it is suspect. I've seen it before. is it the correct plug for the engine?

In any case, that plug is toast and for those very few miles (ok, kilometers), there's a problem.

 

[Hootbro]

Is this the same replacement engine the dealer double filled it (10 quarts) with engine oil not realizing it came with 5 quarts already installed?

If me, I would not just leave it as one plug replaced, but replace them all.

 

[Thinback]

There looks like there is a ball of metal at the base of the electrode.

 

[Maximus Gladius]

Remember, this is the engine the tech made the mistake of topping up the oil to 12L and then I drove it 1500 kms before doing my first oil change. They took it back and supposedly took off the intake and pulled the plugs and cleaned things up.
I don’t normally red line it but it is happiest when the rpm’s are up there on highway inclines or when passing on the highway.
I also had a new coil but checked the ohms of the old coil and the new and the numbers were the same so I put the old coil back.

 

[Maximus Gladius]

This plug and me are going to have a sit down with the service manager to discuss the need to investigate further.

 

[Maximus Gladius]

Engine tick?

No engine ticks. Super quiet cold or hot

 

[ShadowsPapa]

Remember, this is the engine the tech made the mistake of topping up the oil to 12L and then I drove it 1500 kms before doing my first oil change. They took it back and supposedly took off the intake and pulled the plugs and cleaned things up.
I don’t normally red line it but it is happiest when the rpm’s are up there on highway inclines or when passing on the highway.
I also had a new coil but checked the ohms of the old coil and the new and the numbers were the same so I put the old coil back.

I've driven mine through mountains, crazy traffic (Orlando, Atlanta, etc.), and live where the hills cause semis troubles and you have to really try to get around quickly as it might be your last chance in miles, and have never had a need to go over 5,000-5,500.
Would love to know what sort of grade that was or what you were attempting that it took redline on a highway.
When I talk "happiest at higher RPM" for me that's more like 3,000-5,000.

In any case, if that's a semi-regular thing, don't expect long life.

That plug is crap - toast, actually physically damaged, I agree, replace them all.
But that center electrode in what I call 30,000 miles - that's just crazy.

 

[Maximus Gladius]

In any case, if that's a semi-regular thing, don't expect long life.

It’s rare, but it occasionally happens. I’d say the grade of incline is about 6% and the truck just wants to go…and maybe it’s the kids shouting FASTER DADDY, FASTER!!

 

[PuddleJumper]

I'm sure the engine is fine and you found the culprit. the plug looks to be as worn out and abused as one can get before just plain failure. its condition match with the environment you run your truck and the fact your truck was overfilled with oil at one point. I'd just up the interval at which the air filter is changed if your seeing dirtier air than the rest of us and then just change all the plugs, odds are they all look like that or close too. This was probably a problem that you found early cus like me you actually let the damn thing stretch its legs. but man you seem to have the trouble maker, am I right that your also on your 3rd PS pump or was that someone else?

 

[PuddleJumper]

It’s rare, but it occasionally happens. I’d say the grade of incline is about 6% and the truck just wants to go…and maybe it’s the kids shouting FASTER DADDY, FASTER!!

need an excuse for hemi swap lol. wring her out dammmit.

 

[Maximus Gladius]

am I right that your also on your 3rd PS pump or was that someone else?

That’s me!
edit: I’m driving on #4.

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