2018 JL Wrangler Rubicon 3.6L engine trouble

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I agree about statistical probability. There's a feeling though, that's refusing to leave me, that IN GENERAL, the perception that American cars are under engineered vs Japanese and European counterparts is not too far off the truth
I dunno, there's also a perception that they've all approached each other: Asian imports aren't as good as they were, and domestic isn't as bad as they were. The Germans, eh... they were always well engineered, but sometimes one wondered what the design goal had been. [I'm joking!]
 
so basically you abused the jeep and now trolling for lols on bitog?
My DD is a JL Rubicon & have no interest in driving that fast, high CG … 4.10 gears …
Saw a guy tested on salt flats and said engine limiter held him to 97 mph … with the aerodynamics of a toaster … that driveline is stressed … not a car …
 
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so basically you abused the jeep and now trolling for lols on bitog?

For "entertainment purposes" means I don't seek advice on what to do. And I also think it's peculiar and unusual - entertaining - for modern engine to have broken rocker arms at 28k mi on the odometer

I don't believe I've abused the car. Using WOT at freeway speeds to pass or overtake cars on the freeway might constitute a Heavy Duty operation mode, but it is far from extreme. Even if done for hours at a time. That my oil pressure AND engine oil, transmission oil, and coolant temperatures stayed good confirms that. My almost 30 year old Mercedes has beeb driven the same way for the past 6 years, btw. Knock on wood, stoically without complaining

That I drove 300+ miles - I had no choice, needed to get home - wife and 3 year old in car. I don't believe that driving 80-95mph on misfiring engine is significantly worse than driving 60-70mph.

This happened over a labor day weekend. I called on Sunday to a Washington DC dealer to check if, maybe, service department will be open on a Labor Day (Monday). Even though I re-asked, I was still assured that it will be. I showed up 10 min before opening on Monday and, of course, it never opened. So, 10 am we loaded up and drove 360 miles back to home state. We weren't sticking around for another 2-3 days in DC.
 
WOT isn't abuse. Driving with a missing cylinder can be--if it's injecting fuel it could be bad for the cat. If something mechanical is broken off and bouncing around in the cylinder, it could do untold amounts of damage.

Driving on without diagnosis can be abuse. "Knowing" that you can is different.

I think you might be right though, driving 80 instead of 60 would have been the same damage to the engine, whatever the root cause was. The question though would be: how'd you know it was safe to drive at all?
 
so basically you abused the jeep and now trolling for lols on bitog?
Yep...

If the OP had owned it, he wouldn’t have hammered it, full throttle at well over the speed limit, for hours, with a misfire and CEL.

But it’s a lease. So he abused it.

This tells you all you need to know:

I'm posting this for entertainment purposes.
 
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My DD is a JL Rubicon & have no interest in driving that fast, high CG … 4.10 gears …
Saw a guy tested on salt flats and said engine limiter held him to 97 mph … with the aerodynamics of a toaster … that driveline is stressed … not a car …

That's what I've found out, about 97 mph is a maximum. I think electronic governor is set at 99mph(?). Driving 80-95mph on a freeway when traffic allows make a trip less "droning" and a bit more lively. You also shave off about half an hour over there course of several hours.

At 95mph, I think the engine is turning at 3-something-K RPM. I'd wager, off-roading in a hilly terrain would be more taxing overall
 
WOT isn't abuse. Driving with a missing cylinder can be--if it's injecting fuel it could be bad for the cat. If something mechanical is broken off and bouncing around in the cylinder, it could do untold amounts of damage.

Driving on without diagnosis can be abuse. "Knowing" that you can is different.

I think you might be right though, driving 80 instead of 60 would have been the same damage to the engine, whatever the root cause was. The question though would be: how'd you know it was safe to drive at all?

First thing I checked if there is oil pressure - check. There wasn't a mechanical metal sound from the engine, just vibration due to misfire - check. Metromile insurance "metronome" - plugs into OBD port - told me the code was for a misfire on cylinder #6. So, my understanding was, that the issue is tied to that specific cylinder only, and that computer "must" know not to supply fuel to it. My MB has a distributor ignition. If similar situation occurred on it, I would rather jump from a 3rd story building than to let missing cylinder flood with fuel, with all of the potential consequences. But on Jeep - modern computers and a lease - so it was a well weighted gamble to proceed with a drive, in my mind
 
That's what I've found out, about 97 mph is a maximum. I think electronic governor is set at 99mph(?). Driving 80-95mph on a freeway when traffic allows make a trip less "droning" and a bit more lively. You also shave off about half an hour over there course of several hours.

At 95mph, I think the engine is turning at 3-something-K RPM. I'd wager, off-roading in a hilly terrain would be more taxing overall
Rubicon’s have 4:1 transfer cases … geared way lower than other Jeeps … so with 4.10 pumpkins and a ZF8 … they off road with ease. Had mine in 4WD for about 40 miles in the last week … they are amazing in the soft stuff ✅
 
It's a lease, so that means its beat on only slightly less than a rental.

Pentastars seem to have "weak" rockers. Weak might not be the right term but they seem to fail a bit more often than what you hear of for other engine families. Still. Not sure how many Pentastars have been made, nor the failure rate, but I'm guessing it's still pretty low. It's a mechanical creature, stuff does fail. It's annoying, but expected in the scheme of things.
FCA announced in February 2019 they had made 10 million Pentastars.

I have seen a few v6 rocker failures on various Mopar groups on Facebook, but considering how many of them there are the failure rate seems incredibly low.
 
I can't believe you put family in jeopardy doing 95 in a vehicle that wasn't designed nor is it safe at those speeds. Care less about the Jeep after reading this.

Mate, you're kidding, right? Your probably picturing a Wrangler from1981, with bad dampers. The 4 door JL Rubicon is easily controlled with one hand, at 95 mph. You can even dart/point and squirt between cars - no problem. Obviously it isn't a Miata, but it's not a Soviet UAZ either. The all-terrain tires are speed rated to 99mph. I'm pretty sure that with all-season highway tires, which most Wranglers are sold with anyways, it can cruise 110 mph, traffic permitting, safely, all day. Fuel economy will be even more non-existent though.

At any rate, he's back, alive and kicking:
PXL_20200915_214124579.jpg


Here's Tech's notes:
PXL_20200915_221233643.jpg

PXL_20200915_221302700.jpg
 
Typically when a CEL comes on something is wrong. To beat on an engine with a CEL on of another 300 miles is not a good idea, in fact if anything the vehicle should have been driven easier and diagnosed ASAP.
Drive i like you stole it .
 
Mate, you're kidding, right? Your probably picturing a Wrangler from1981, with bad dampers. The 4 door JL Rubicon is easily controlled with one hand, at 95 mph. You can even dart/point and squirt between cars - no problem. Obviously it isn't a Miata, but it's not a Soviet UAZ either. The all-terrain tires are speed rated to 99mph. I'm pretty sure that with all-season highway tires, which most Wranglers are sold with anyways, it can cruise 110 mph, traffic permitting, safely, all day. Fuel economy will be even more non-existent though.

At any rate, he's back, alive and kicking:
View attachment 29428

Here's Tech's notes:
View attachment 29429
View attachment 29430
Nope not kidding. 26% rollover rate, removable doors, poor crash tests etc.


Facts remain a top heavy vehicle speeding down the highway with small children that is marginal at best for safety is never a good idea
I owned one SUV and drove others and can tell from experience a top heavy vehicle can get away from you the minute you get to comfortable
 
I wonder what the deal is with #6 plug being covered in oil. For some reason I don't think this is the end of this story.

Maybe somebody spilled oil on it when they did the oil change? Wouldn't be the first time that's happened.
 
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