[Chris Juniper]

Just looking to see how common this is in the KL cherokees. I'll preface this by saying I have a limited knowledge of the inner-workings of engines. Three weeks ago my 2016 v6 cherokee 98k miles, threw a check engine light, the code was P0306, misfire on cylinder 6. I brought it to a local shop and they figured it was spark plugs and replaced all of them and cleared the code. A week later the same light and code came back on so I figured my best bet would be taking it to a Jeep dealership. Long story short the tech called me back yesterday and said they were able to confirm I had a bad cylinder head, I don't remember 100% if he said it was cracked or just bad but I digress. Looking at a $3,000 bill to fix it, which I'm doing because I don't have much of a choice. I'm just curious if this is a common issue, and if there's anything I can do in the future to prevent this from happening again, or is it just **** luck.

 

[Mark_]

Just looking to see how common this is in the KL cherokees. I'll preface this by saying I have a limited knowledge of the inner-workings of engines. Three weeks ago my 2016 v6 cherokee 98k miles, threw a check engine light, the code was P0306, misfire on cylinder 6. I brought it to a local shop and they figured it was spark plugs and replaced all of them and cleared the code. A week later the same light and code came back on so I figured my best bet would be taking it to a Jeep dealership. Long story short the tech called me back yesterday and said they were able to confirm I had a bad cylinder head, I don't remember 100% if he said it was cracked or just bad but I digress. Looking at a $3,000 bill to fix it, which I'm doing because I don't have much of a choice. I'm just curious if this is a common issue, and if there's anything I can do in the future to prevent this from happening again, or is it just **** luck.

Hi,

We've seen quite a few members post about similar misfire codes here. If not spark plugs or coils, it has been more about rocker bearings / cams / valve seats than anything else.

Did they specifically explain why they know it's a bad head, and what is bad about it ?? They may have meant valve seats, requiring a new head (low compression on that cylinder). Just know a cylinder head can be machined, if you find the right shop to get this done. Dealerships have a book that says replace head, but that hurts when warranty is out...

I would ask them if they mean valve seat problem. Then I would look for another shop where they know Pentastar engines and can possibly get the head repaired/machined, if cheaper than replacing...

 

[Chris Juniper]

Hi,

We've seen quite a few members post about similar misfire codes here. If not spark plugs or coils, it has been more about rocker bearings / cams / valve seats than anything else.

Did they specifically explain why they know it's a bad head, and what is bad about it ?? They may have meant valve seats, requiring a new head (low compression on that cylinder). Just know a cylinder head can be machined, if you find the right shop to get this done. Dealerships have a book that says replace head, but that hurts when warranty is out...

I would ask them if they mean valve seat problem. Then I would look for another shop where they know Pentastar engines and can possibly get the head repaired/machined, if cheaper than replacing...

Well in hindsight maybe I should have asked more questions, though I did not know what questions to ask, I just wanted my car fixed and it should be done this afternoon. The only other things the Tech told me were that they confirmed it wasn't an electrical issue, ignition coils etc, and that they did some sort of test on the cylinder and found an 80% leakage/loss of fluids in that cylinder.

 

[sanghill]

Even though the spark plugs are advertised for 100K miles I think they should be replaced a lot sooner, say about 80K miles.
A worn out spark plug will not damage a cylinder head, at least I don't think so. Just misfire.
Replacing the spark plugs incorrectly could damage the cylinder head, left dirt in the area of the spark plug, cross threaded the plug when installed, cracked a plug ceramic insulator,
didn't use a torque wrench. Didn't replace the intake manifold seals and ended up with a vacuum leak. However, I would expect a dealership mechanic to be better trained.
Like Mark_ said it could be the rocker bearings.
If the coolant level was ever low, or there is air in the coolant you can warp a cylinder head.
Once they take it all apart we should have a better idea of the problem and the cause of the problem.
In 6 years on this site I don't think I have heard of any cylinder head problems, except to the rocker bearings.
When I had a replace the engine in my Oldsmobile I put in a 'crate engine'. It had a better warranty than the original engine.
I think it was $3K or $4K but the new engine almost has 200K miles on it.
Depending on the prognosis for your engine this may be a viable option.

Based on your Post #3 I think the entire engine should be replace.
Coolant in the combustion chambers or in the oil pan and system will ruin the engine.
80% of coolant running around where it doesn't belong is a disaster.

This is all just my opinion which is worth about what you paid me for it.

 

[Mark_]

Well in hindsight maybe I should have asked more questions, though I did not know what questions to ask, I just wanted my car fixed and it should be done this afternoon. The only other things the Tech told me were that they confirmed it wasn't an electrical issue, ignition coils etc, and that they did some sort of test on the cylinder and found an 80% leakage/loss of fluids in that cylinder.

Ok... guess I didn't realize the work was being done as we speak. They probably did a good diagnosis, from what you recall there. I don't know the cost difference between replacing or repairing a cylinder head, but now at least they are fixing it. Hopefully

So to answer your initial question ; I guess it is a known issue. How prevalent ? Hard to say from where I'm sitting, but enough that FCA should make changes to these engines, if not done already...

 

[Desoto]

They thought they had corrected these issues prior to the 3.2 production. n’est jamais arrivé!
Most of the 3.6 issues followed the 3.2.

 

[jim383]

I had no problems at all with my 2014 / 2015 3.2 engines. So far my 2.0 turbo hasnt skipped a beat. I got a big tree in back yard i knock on every day lol.

 

[Mark_]

<snip> n’est jamais arrivé!<snip>

Did you have to Google translate that ? If not, you get a perfect score.

Thanks for confirming it never happened... though it should've...grrr... Those are expensive repairs :-(

 

[ritchie1230]

Just looking to see how common this is in the KL cherokees. I'll preface this by saying I have a limited knowledge of the inner-workings of engines. Three weeks ago my 2016 v6 cherokee 98k miles, threw a check engine light, the code was P0306, misfire on cylinder 6.A week later the same light and code came back on so I figured my best bet would be taking it to a Jeep dealership. Long story short the tech called me back yesterday and said they were able to confirm I had a bad cylinder head, I don't remember 100% if he said it was cracked or just bad but I digress. Looking at a $3,000 bill to fix it, which I'm doing because I don't have much of a choice. I'm just curious if this is a common issue, and if there's anything I can do in the future to prevent this from happening again, or is it just **** luck.

Hello,
I had a similar experience. replaced the plugs, cleared the code. Took it to the dealer...bad cylinder head. They took it to a machine shop and were able to "recondition it" $2500 later the problem was corrected.

 

[T-HAWK*LTD]

Sorry to be so repetitive,

This could be an issue with carbon build-up on the valve stems, (not allowing them to close completely), that gives the indication of among other things a bad head.

"They took it to a machine shop and were able to "recondition it" $2500 later the problem was corrected."

Could be one of the things they did was to clean the valve stems.

It might have been the only thing they did.

 

[Utah_Jeep]

Back in July, I brought my 2015 Cherokee TH with only 66,000 miles, to the dealer for a check engine light. Cylinders 5 & 6 were misfiring, they replaced the coils and sent me on my way. Here I am just 3500 miles later, the check engine light is on and the dealer says I need a new cylinder head as well as a slew of other parts. I purchased an extended factory warranty and am hopeful they will cover this as the contract says it should. However, I had to put up a pretty big fight with the service rep to have the coils covered back in July even though I had documentation that stated this was covered. I'll follow up when I hear back

 

[toofastgtp]

Sounds like you were hit with the rocker arm/cam failure the 3.2/3.6 are known for. Did they say what exactly failed in the head?

 

[Utah_Jeep]

Sounds like you were hit with the rocker arm/cam failure the 3.2/3.6 are known for. Did they say what exactly failed in the head?

They have not given me a detailed diagnosis. They just gave me a list of parts it needed. I find this typical of most service shops within a dealership. They are so dismissive and don't go into great detail about what's wrong, rather just what needs to be done.

 

[Flybynightcru]

They have not given me a detailed diagnosis. They just gave me a list of parts it needed. I find this typical of most service shops within a dealership. They are so dismissive and don't go into great detail about what's wrong, rather just what needs to be done.

First and foremost, welcome!!! I'm also in Utah, and was just wondering what dealership you are using??? There are some good, and some bad situated around the valley...

 

[Utah_Jeep]

First and foremost, welcome!!! I'm also in Utah, and was just wondering what dealership you are using??? There are some good, and some bad situated around the valley...

Salt Lake Valley on State St.

 

[Utah_Jeep]

First and foremost, welcome!!! I'm also in Utah, and was just wondering what dealership you are using??? There are some good, and some bad situated around the valley...

Where would you recommend?

 

[Flybynightcru]

Where would you recommend?

Well, I bought mine from Layton Hills Chrysler Dodge Jeep Ram, and if I had something major happen, which I haven't, I would use they're shop I think. I also got extremely lucky, with their free Lifetime Powertrain Warranty, and also Max Care. I haven't heard anything bad about SLV CDJR, so that's probably a good thing. That's definitely a bummer about your cam bearings, that's not a cheap fix, and the worst part about it is, it is such a well known, and unfortunately, a far too common issue. Part of the reason I took a chance with the brand new 2.0T in my 19 Trailhawk, and am extremely happy, and glad I did. Best advice out there is, stay on their butt, and demand action, and if you are still in warranty, they have an obligation to fix it. Good Luck, and keep us posted.

 

[JeepCares]

Back in July, I brought my 2015 Cherokee TH with only 66,000 miles, to the dealer for a check engine light. Cylinders 5 & 6 were misfiring, they replaced the coils and sent me on my way. Here I am just 3500 miles later, the check engine light is on and the dealer says I need a new cylinder head as well as a slew of other parts. I purchased an extended factory warranty and am hopeful they will cover this as the contract says it should. However, I had to put up a pretty big fight with the service rep to have the coils covered back in July even though I had documentation that stated this was covered. I'll follow up when I hear back

If you require any assistance while working with the dealer for repairs, Utah_Jeep, send us a private message. We'd be happy to help.

Kate
Jeep Cares

 

[jcool001985]

@Utah_Jeep that is really a shame the dealers are now forcing cylinder head replacement vs just simply replacing the roller rockers and camshafts which is far cheaper than a whole new head. Very common problem on the pentastar engines is failure of the needle bearings within the roller rocker. Motorcity mechanic on YouTube goes into great details on the failures and the repair. I would press the dealership to replace all the roller rockers and any damaged camshafts while they are in the engine. I had the unfortunate experience on my 2014 V6 to have a misfire on one side of the engine. Before I knew the actual failure they replaced just that side of roller rockers and cams. 10k miles later and out of warranty the other side had a misfire. Had to fight FCA and the dealership for over 3 days to finally get them to cover it. They "claimed" they only replace what is broken at the time even though the engine tech told me it's a well known issue and all roller rockers will eventually fail if not replaced.

The pentastar V6 is a nice smooth engine and tows well but I will never buy another. Have been through 2 oil coolers as well.

 

[Mark_]

@jcool001985 : I've read here on the forum that, sometimes with the Pentastar, the problem is a valve seat. Options then are either replace the head (dealer preference), or have the head machined which is somewhat cheaper.
I guess a compression test would quickly tell you if it's more valve seat, or not.