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Found On Road Dead: Spark Plug Electrode broke, now I need a whole new engine?

I mentioned this in another thread but this thread title is more accurate and I need more info.

A few months ago I got a Check Engine Light. I did notice the truck running a little roughen cold mornings, but once it warmed up fine. Took to the dealership, on first glance they told me cylinder was bad, replacement would be covered by warranty. Get a call a few days later, NOPE not covered by warranty, a spark plug electrode (which isn’t covered by warranty) caused the damage to the cylinder, and by the way, you now need a new engine because it also damaged the crank arm. That’ll be $12,000 please. Finally Ford Customer Care offered to pay 30% of the repair, bringing it down to $9,000. Still a ton of money to me. I would have just kept driving the engine as it was till it really died if I had known.

So now I have a few different tracks of questioning:
The warranty specifically says that it doesn’t cover damage to warrantable parts caused by non-warrantable parts. The plug was not covered by warranty (Ford ESP warranty from Ford). Is there any way to argue that the spark plug was damaged by combustion of the engine?

This truck is a 2013 Ford F150, with the 5.0L V8. 80K miles, bought at 40K and was certified preowned. I purchased a 7 year, 100K mile warranty at the time from the dealership. It is a Ford ESP warranty.

The Engine Damage was caused supposedly by an electrode that broke off the spark plug and damaged the cylinder head and the crank arm to the point that now I need a whole new engine? Does this sound fishy to anyone? A few mechanics that I talked to seemed confused as to how this could be the case.

Replacing the Engine I’m leaning toward having the truck towed to another shop and having a used engine installed (it they think that’s still what needs to be done). Then probably turning around and selling the truck and trying to get at least some money back. Is this probably my best course of action?

I’m not a rich guy, this will definitely set me back either way, and I’m just trying to figure out my best course of action to get out of this without getting put into bankruptcy.

Right now I can tell you that I will NEVER buy or tell anyone else to buy a FORD vehicle. It is a shame too, because this is my 3rd Ford vehicle, and the year I bought it, my family bought 4 Ford vehicles.

Have you contacted the spark plug manufacturer about this yet?

Motorcraft (spark plug) warranty is only 2 years.

I think they are full of crap. The broken electrode would not cause that much damage. Just because they find a broken electrode, does not mean that the broken electrode was the cause of the damage. It more likely is a product of the damage. The piston rod probably broke first and the resulting collisions broke off the electrode, but a broken rod would have stopped the engine cold.

If you drove the truck into the dealership and it was running quietly with just a little miss, they did something and are now trying to cover their tracks.

Go to the dealer and demand (ask first, then progress to demand as needed) to see the engine. Take a picture of the vinyl tag on the valve cover on the passenger side of the engine, center of the valve cover near the bottom.

Then use google to find out which engine this is. It might not be yours. The tag will tell you if the engine is one of the series of engines used in your truck. Post the picture here along with your VIN here and maybe someone here can help you further.

If you mean the little curved ground electrode on the plug or the porcelain center of the plug, neither of those should destroy an engine. It should be pretty much vaporized by combustion and spit out past the exhaust valve.
I can’t really buy into that scenario at all.

Here are a few photos that the shop sent me: (I can only do one at a time because I’m a newb)
I still need to go down there and see it in person. Very good point keith I need to see the damage and verify that it is actually my engine.

Ask if there’s a used engine available to be installed.

Pucker factor of 10!


You repeatedly mentioned “crank arm”

Clearly something was lost in translation

Do you in fact mean crankshaft . . . ?!

Or do you mean connecting rod . . . ?!

I suggest you either tow your truck out of there and get a used engine installed . . .

Or you hire a lawyer, who will start to send correspondence to the dealership. That might get results. Once letters start showing up with the lawyer’s letterhead, they might quickly decide to eat the entire costs, because they now want to be seen as the good guys

If you get a used engine installed, after it’s up and running, I suggest you immediately plan on offloading the truck, since Ford’s esp warranty appears to be very deficient

Have you already asked the dealer to eat the costs as a goodwill gesture . . . ?!

Have you already contacted the regional manager . . . or zone rep, or whatever he calls himself . . . ?!

And thank you for the pictures . . . it certainly puts some things in perspective


Clearly, the broken center electrode and ceramic sleeve were interfering and caused some damage. How much is the question. It wouldn’t be uncommon for a shop to recommend replacing the whole engine because they have to stand behind the repair. If it were mine, considering it’s a 2013 and drove to the shop, I would have removed the head, fished out the debris, inspected the valves and buttoned it back up. See what happens before going nuclear and replacing the entire engine. It could last the rest of a normal life given its age. If it gets worse or fails outright, then decide if it warrants replacement. Had quite a few similar scenarios in my life of well used car ownership and repair that worked out to my advantage to not take the chance. Just my 2c

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Sadly, this is a legal problem. Hire a lawyer that specializes in consumer protection. The warranty company is trying to weasel out of this repair and you are letting them do it if you take the truck to another shop. Get the lawyers advice before you do anything. Follow that advice. Good Luck

Just a comment; I had an under-warranty engine in a Pontiac with 22K miles that I bought new. Once apart, it looked like the center electrode failed on one plug and burned a hole in the top of the piston. The electrode was gone and a hole 1/2 in diameter was burned through. Did the cylinder go lean and burn the plug? Did the plug fail because it was defective? We will never know but I got a new short block because the car was under warranty (8 days from expiration!!)

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I see one nicked piston and a few damaged valves. Hardly necessitates a whole new engine, especially given that this truck drove into the dealer. It wasn’t towed in with a seized-up motor. In any case, spark plugs don’t just spontaneously “break apart”, especially spark plugs that have been in use for years and tens of thousands of miles. It is much more probable that an engine problem destroyed the spark plug, not the other way around, and they know this.

I would lawyer up ASAP. It sounds like Ford is not going to honor its warranty without some “persuasion”, and a letter from an attorney is the first step to convincing them that repairing your engine will be the cheapest and best option for them. Short of that, I’d find someone who can replace the damaged valves (or install a used cylinder head), clean up the nicked piston, and put the motor back together. Then get rid of the truck, and NEVER buy another Ford product again.


Agree with every thing you said except about never buying another ford that would be like the one bad apple in the barrel & throwing the whole barrel away just because one is bad don’t mean they all are.

Seems like it might need a valve job . . .

As for the cylinder wall . . . measure and if possible, bore out to 1st or 2nd oversize, along with the corresponding piston and rings

I don’t see how the gouges wouldn’t eventually affect the rings

You do NOT see the damaged cylinder . . . ?!

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I don’t see how debris could have gotten from the cylinder into the crankcase and damaged the crankshaft. It would have to get past either the piston rings or the valve seals, and the damage inside the cylinder would be a lot worse. Or am I missing something?

After seeing the pics I think the engine does need to be rebuilt or replaced; probably the latter. The part that concerns me is the nicked cylinder and the nicks on the edge of the piston… If the cylinder wall wasn’t nicked and the piston was only nicked in the middle I would say clean up the head and reinstall it.

Usually what happen when you have a particle in the cylinder it will glow red under combustion and cause severe detonation. That should cause a loud knock.

I wonder (just theorizing) if the plug failure could be due to a faulty EGR system.

I had a similar situation with the 1990 Ford Aerostar I once owned. The engine started missing on one cylinder. The Ford dealer found the ceramic tip on the spark plug for that cylinder had broken off. The plug was replaced. I was suspicious that my problems weren’t over. I was right–there was a hairline crack in the cylinder head. When it happened again, Ford replaced the block and one cylinder head. When I asked the service manager why they didn’t just hone that cylinder wall that was scored, he said it was Ford’s policy to install a new short block. Fortunately, my Aerostar was still on warranty and I was glad Ford installed a new shortblock and cylinder head.

Who’s to know when eventually is so why not wait and see? How much more damage than a replacement engine or even just a slug repair can happen by the time eventually rolls around? I would roll the dice. Even if I end up with one cylinder using some oil, I’m ahead big time compared to $12k.

No doubt the cylinder overhaul would be better but is it worth it for someone paying a pro to do that work? I may be biased, I’ve seen worse sins that survived the remaining life of an engine.

Sucks for OP. Impossible to prove engine caused failure. Yes, a persistant preignition condition can cause this kind of failure but so can dropping a plug during install. Proving either will be next to impossible…