Looks like in that picture you're looking at the top of the piston with a chunk missing showing the top compression ring. The reflection of the smooth cylinder wall makes it a little confusing at first glance. Left side is the reflection off the cylinder wall, right side piston top missing a big chunk.

Interestingly it looks like a clean break and I don't see any melted edges or splattered material from detonation or lean running in that picture at least. It would be good to see what the piston and cylinder head look like when its pulled apart.

 

Bingo, I still contend something happened at JLR South Atlanta. They told me on the phone they pulled the plug on cylinder 6 and it had build up on it, so they recommended changing plugs . Maybe it was a coincidence, but tracing everything back, the other Jaguar dealer believes something happened there as well. Add to that the plug was damaged when I pulled it......

the motor won’t get taken apart, my Indy found a motor with 8900 miles on it. $13k $4k to install. The old motor will go back for core charge. Funny thing, above 2200 RPM, the motor runs fine. No misfires, nothing! I guess I could always ride around with one foot on the brake the other on the gas! They were made to be driven fast !

 

What was the final outcome? Did you have the engine replaced?

 

Well...Same thing happened to me. Something took a chunk out of #1 piston. No hot spots, just a piece missing and a scored cylinder wall. Engine was replaced. Extended warranty company originally agreed to pay, but JNA ultimately picked up the tab despite the car being out of OEM warranty for 5 months. I'm still scratching my head over that one. BTW, and rightly so, there was no consideration that the tune might have caused the problem.

 

Wow when did that happen? Was it over the last few weeks? How long to fix?

 

End of October. Warranty issue resolved within a week and engine arrived about 5 weeks after that (~12/15). They accidentally dropped one of the cats and replaced both for free as well. Car was returned in immaculate condition.

 

Glad everything worked out. Was really surprised by this as I didn't catch you mentioning it on the forum before.

 

Didn稚 want to launch any unfounded warranty speculation until the matter was fully resolved.

 

wow, what was the cause?? it wasnt tune related right??

 

Not tune related as there was no evidence of detonation. They have no clue.

 

That’s our specialty. Sounds like they treated you well, and the outcome is about as good as it could be (minus understanding the failure mode.) And they didn’t spot the operation overthruster.

 

Happy New Year Unhinged! Good to see both the extended warranty company and JLR both accepted responsibility for a bad motor. Was the extended warranty from JLR (dealer) or independent company? I ask before I have a JLR dealer extended warranty. How many miles on your motor? Did you use this repair to replace your clutch or was that not something you considered? What was the issue with your motor that raised your awareness to a problem​​​​​​? Curious minds want to know? All the best in this new year.
Frank

 

Sorry to hear about the engine. Amazing good luck with free replacement, I am glad it worked out for you.

I am hugely surprised it played out this way. How did you pull this off and why did your well-publicized and very noticeable tune did not become an issue? Why did the shop not check a very obviously lowered car, with a custom exhaust, custom pulley, custom disks, polished SC for ECU tune? Why JLR did not send out escalation tech to check it out? You can tell your car is tuned by just looking at it from 10 feet away. Did you unbolt everything before getting it towed to the shop?

What makes you say that? You have one of the most tuned AJ126 engines on stock hardware, well past anything JLR pushed with that hardware on their own, and you don't think unexplained catastrophic internal engine failure well out of break-in period has anything to do with the tune?

Ok, let assume it was not a tune. What else could it be?

Did you or someone else money-shift it?
Known defect in metallurgy? That would explain why they stepped up and volunteered to fix it. This would also mean the rest of us have ticking time bombs.
Oil starvation localized to that cylinder? More AJ126 engines would have failed this way by now, as they are also found in other JLR cars.
Debris ingestion? You know better than dropping a washer down the cylinder while changing spark plugs. Where would it come from?
Hot spot? Theoretically should be visible with the probe after the fact. Also why would it form, plugged coolant passage?
Lean out without detonation leading to excessive heat? Never seen that myself, but theoretically possible. I think the piston crown would be partially melted. Plus you push the car, if lean out was the case I would think it would cause detonation under load.

Did you get your hands on the old engine and opened it up? Did you do oil analysis close to the failure and did it show anything unusual? What oil were you running?

 

My dealer has always known about the overthruster.

I purchased the extended warranty from the dealer. ~40k miles on the car. The mechanic (the only one the dealer will let touch the F-Type) suggested a clutch replacement, by I only have 18k on that clutch, it seems to be working fine, and I want to test fit my custom proto-type clutch from SPEC Clutch when I need a new one. The puff of smoke in the rearview mirror, the CEL immediately illumminating, and the mildly rough running engine were all an immediate indication of a serious issue. Mechanic at first thought it might be a blown head gasket.

My service team knows everything that has been done to the car over time. The mechanic even saw the changed tune flag and made certain I had the OEM tune back on it before they updated the tune after the new engine was installed. Sorry, no evidence of detonation or overheating. The mechanic theorized that it was a small casting imperfection of some sort in the head or SC that could have broken loose. I did not get to open up the engine. JNA got that back. Given the occurence that inspired this thread, these may not be isolated occurences (tuned or not).

I believe I have mentioned it a number of times before: the sales & service experience that I have received from Jaguar of West Columbia, MD has always been exemplary. If they ever make a 2 Door Defender with MT, I'll be going right back there to get it. I'm also not planning to take my service needs anywhere else.

 

Thanks Unhinged for the information. I purchased my jag with 30k miles and a two year extended warranty. To dates: pinion seal replaced and the passenger side carpet to be replace this month weather permitting. All the goodies installed on new motor including polished SC.
Frank

 

I wrote a response to this, I guess I never hit post. The Indy shop took the car apart, got the used motor , then a severe Covid outbreak at the shop shut everything down for a few weeks, then the holidays happened , I was told mid January , so I am expecting an Ftype any day now!

 

2 Jag shops and 2 Indy shops couldn稚 explain the damage to my piston, just saying . foreign object of unknown origin was the most prevelant theory!

 

We both had a UFO encounter (unidentified foreign object).

 

Update- everything back together, motor seemed fine but now I have an occasional misfire on 4&5. Replacing the coil pack and try again. Motor sounds great!

 

I had the same problem on my new replacement engine. The problem was resolved with the most recent Jag software update to the ECU. That massively muted the exhaust exhaust sounds, but VAP resolved that unwanted side effect. Try swapping the coils to a different location before you potentially waste money replacing them.