Jeep Enthusiast Forums banner

Potential 2012 Pentastar issue?

162K views 649 replies 146 participants last post by  AZBob 
#1 ·
Well I have been noticing a ticking noise coming from the drivers side of the engine that has grown louder.

Did a search and lo and behold here's what was found so far.........

http://www.wranglerforum.com/f33/update-on-ticking-pentastar-new-head-137608.html

http://www.jeepforum.com/forum/f96/2012-rubi-check-engine-light-1299151/

Felt it was time to start a new thread with a different title as there appears to be an identified issue with a head replacement as possible solution.

Wanted to check in with other 2012 owners and hear what ya'll have to say.

07-11 JK 3.8 owners go easy on us early penta jesus adopters.:laugh:

Will be setting up a service appoint as soon as I can.
 
#2 ·
Need more info. Manual? Auto? Does it do it in gear? Does the time between ticks decrease when you give it gas?

Mine knocked (but ticking would be accurate, too) when the Jeep wasn't in gear. I thought it was the engine, but it ended up being the throw-out bearing, which has been hit or miss with the JK since '07. Got it fixed under warranty and the noise is gone.

EDIT: Nevermind. Read your sig in your profile and you've got an auto. Either way, take it to the dealership.
 
#3 ·
auto tranny

Noise at idle and increases in speed with engine rev's while Jeep is sitting still.

Not mine but here's examples





Just to clarify... I'm a gear head and have rebuilt a few engines in my day.(even an ol 1952 Dodge M-37 army truck straight 6)

Most definately valve train noise. And it's getting louder.
 
#5 ·
My Jeep is still in the shop getting a new head and parts. It ticked but not as loud as that video. Another funny symptom mine showed after the check engine light/ticking noise started. My "Eco" indicator never came on.
 
#7 ·
Caveat: I don't know squat

I don't have answers, only questions.

Could it conceivably be due to something being up with the fuel injection system? The sound seemed to increase in the first video as the camera hovered over that rectangular body with the six black lines coming out of it. My guess is that the box is part of the fuel system.

If the engine is idling at around 800 RPM, then that means 4,800 cycles per minute are going on, divided by two (4-stroke engine), giving 2,400 power strokes per minute. Divide that by 60, and that's 40 fuel-pulses per second.

A 40 Hz vibration (rapid ticking) would sound pretty close to the frequency heard in that first clip. I know what a 60 Hz pulse-sequence sounds like from MIG welding, and various electronic applications - and that's not far off.

The valve train idea would be perfectly within the range of this sound, as well - but I don't know. The reason I'm thinking fuel system is Rivet's comments about the "ECO" light, but I'm not sure at all if the economy light is based directly off fuel flow or RPM. If it's fuel flow, then what would air bubbles in the system do to it, or how the engine runs? If it's RPM, then maybe it is more an issue relating to the valve timing system.

Not claiming any knowledge, here - just generating ideas. Even being wildly wrong helps, sometimes. :)
 
#498 ·
I don't have answers, only questions.

Could it conceivably be due to something being up with the fuel injection system? The sound seemed to increase in the first video as the camera hovered over that rectangular body with the six black lines coming out of it. My guess is that the box is part of the fuel system.

If the engine is idling at around 800 RPM, then that means 4,800 cycles per minute are going on, divided by two (4-stroke engine), giving 2,400 power strokes per minute. Divide that by 60, and that's 40 fuel-pulses per second.

A 40 Hz vibration (rapid ticking) would sound pretty close to the frequency heard in that first clip. I know what a 60 Hz pulse-sequence sounds like from MIG welding, and various electronic applications - and that's not far off.

The valve train idea would be perfectly within the range of this sound, as well - but I don't know. The reason I'm thinking fuel system is Rivet's comments about the "ECO" light, but I'm not sure at all if the economy light is based directly off fuel flow or RPM. If it's fuel flow, then what would air bubbles in the system do to it, or how the engine runs? If it's RPM, then maybe it is more an issue relating to the valve timing system.

Not claiming any knowledge, here - just generating ideas. Even being wildly wrong helps, sometimes. :)
your 40hz theory is exactly how often a valve opens.

Makes sense that only one head is being replaced if there is a casting issue, the heads are side specific due to the exhaust manifold being cast with the head as one unit. There is a left head and right, so a casting issue on one side is not out of the question.
 
#8 ·
My check engine light/ ticking was happening well before the ECO light stopped coming on.
I do not think that ticking is from the injectors. Yes the injectors do make noise but the ticking I was experiencing was more of a valve chatter. And it didn't start till I had about 8 thousand miles and at cold starts it was really noticeable. And the valves for the #2 cylinder were "burnt up" according to the tech that is working on my jeep.
 
#245 ·
Just picked a buddy from Jeep, same diagnosis following engine light and rough idle on his '12 Grand Cherokee with penta & 24K on clock. Tech told him 81 vehicles are ahead of him to receive the backordered parts nationwide as a result of a STAR inquiry (tech website). Among the parts was a right side head. Hold long have guys been down?
 
#9 ·
JJAMISON_ said:
guys if you own a 2012 jk/jku and it ticks i'd be calling the dealer. warranty it. i wouldn't wait on a recall.
Word up. Can't believe guys with NEW jeeps would rather come on here and ask some couch mechanics instead of taking it to the dealer. There are a lot of qualified guys on here but damn, let someone look at it! Taking my 12 to the dealer to do a leak test today so I will be bringing this up to the guys to have them take a gander. 4200 miles. Drive it til it blows up!
 
#10 ·
Yep called the dealer and have an appointment.

The reason I started the thread was as a "heads up" to the folks who have 2012's and to see if anyone perhaps had the issue.

Perhaps should have been a bit clearer in my initial post.
 
#11 ·
Dude, ALL JKs have had ticking issues. My 2011 ticked so bad when it was new that I came within a hair and taking it in for a service visit. This isn't a new issue that just started with 2012s.

I ended up changing from synthetic to dino oil, and the tick got much less pronounced. Next thing I'm going to try is going from 5W20 (water) to 5W30 and I'm betting it'll quiet the ticking down even more.

But yes, if you are truly concerned, take it to the dealership and get it documented. That way, IF it does blow up at 40K miles you have documentation that you were concerned about it from the beginning. I will say, if you spend as much time with the "new" Chrysler engines (1999 - present designs) as I have you'll start to see that they don't have the best reputation for being long-life engines. Grenading valvetrains before 150,000 miles is very common, and there are a few bottom end problems as well but it's not as common as the top end problems. The new stuff doesn't seem as robust as the older Chrysler designs. That's one reason I'm not that unhappy with my 3.8.

Good luck.
 
#12 ·
There are specific issues with the new engine that apparently involve the driver side head. search and you will find a number of folks getting a head replaced along with the parts needed to do the replacement and the timing chain.

one source (dealer) said it was because of bad valves that were sticking, causing carbon buildup, pre-ignition and other problems. though there seems to be a prevalence for cylinder 2 so i dont see how bad valves would only manifest themselves in one cylinder of the motor.

one report even has dealers pulling new jeeps off of the lot to do repairs before selling them.

currently problems seem to revolve around jeeps produced in july and august of 2011.
 
#16 ·
For what its worth, I did a search on just the engine unrelated to Jeep as people keep saying this is a first year engine. It is not. It has been in the charger, WK and other applications for a couple of years. Newer? Yes, but not first year.

That being said, there are a lot of discussions related to the 3.6 ticking but I cant find one TSB or recall related to it. There are plenty of people saying they are taking it to the dealership but no one seems to post results. As such, it makes me wonder if they are being told this is a normal sound.

I dont have the sound at all in mine, but if I did, I would take it to the dealer, have them look at it, keep the results in writing from them for peace of mind. This is a problem that most certainly will not rear its head (more often than not) until warranty is long gone.

I had an old dodge with a 360 that would tick like crazy until the oil was changed. It would quiet down for about 4k miles and come right back until the oil was changed. Lasted this way for about 100k miles with no issues.

My jeep is 20 years newer and I wont tolerate that, so if I get this same issue, i will be documenting it and making the dealer address it. Everyone should do the same.
 
#23 ·
For what its worth, I did a search on just the engine unrelated to Jeep as people keep saying this is a first year engine. It is not. It has been in the charger, WK and other applications for a couple of years. Newer? Yes, but not first year.

That being said, there are a lot of discussions related to the 3.6 ticking but I cant find one TSB or recall related to it. There are plenty of people saying they are taking it to the dealership but no one seems to post results.
With all your searching you did, I don't know how you missed all the threads and posts where guys have 'posted results'. There are a few of us here that have gotten/getting new drivers side head and misc. parts.
 
#17 ·
I took my '12 into the dealership today at lunch to have them listen to my ticking, (which is exactly the same as the videos already posted). the tech. listened all over the engine with a scope and confirmed the tick. They had not had one in like this before and would only speculate what it could be. They are going to diagnose the noise over the next couple days and get back to me.

FWIW: 2012 Wrangler 2-door. 9-11 build date. 6-speed manual, just under 6k miles and has been ticking for quite a while now.
 
#19 ·
Mine has done it since around 1000 miles. Never thought to much about it thought it was a jeep. But I have over 12,000 on it now.
 
#20 ·
Mine has done it since day 1. I took it to the dealership they checked it out and didn't find anything wrong. I questioned it and so we went out onto the lot with a bunch of keys and started up 4 2012 JK's and every one of them sounded identical. We then started a couple of Grand Cherokees and they had the same tick as well. The conclusion was that it's normal for the Pentastar.
 
#22 ·
Took the Jeep to the dealer today with low expectations as to their ability to look into the issue(based on my previous dealings with them). My goal was to at the minimum have the issue documented.

So I kid you not, here is what I was told by the service advisor:

"The ticking noise is normal"

That "you hear it more as your Jeep is lifted"(I don't have any lift kit)

"These Pentastars make more noise when they're cold"


Unfortunately I dropped the Jeep off as my schedule was tight today so I could not hang around and watch them.

I politely thanked them, signed the paper work, took my copy and left.



To add insult to injury... I stopped off at the local autoparts store on the way home to pick up some parts for the TJ.

The youngster (21yr old) behind the counter had seen the JKUR pull up and asked how I liked the 4 door. Told him everything was great but having a ticking issue with the Pentastar engine.

He then proceeded to tell me that I should have it looked at as Chrysler had some problems with the drivers side head on the Pentastar. To further rub salt in an open wound he desicribed the issue in detail as he had seen this problem pop up on some of the Mopar/Dodge forums.


We'll this ain't my first rodeo and realize that a war is rarely won in the opening skirmish so I've set my sights on a loooong battle to get my Jeep fixed.


Stay tuned..........;)
 
#24 ·
Dropped mine off tonight to have leak test done and have them listen to the engine jic. Three techs hanging out after hours near shop door. Walked up and chatted for a few. Their response about the 3.6 potential problems...."they all click and tick...nothing to do about it except take the motor apart and clean it. There is sand in all of the motors...."

WTF!?! They build the damn things at the beach? No worries, hope it blows and I'll drop in a 4BT or 6.4 :). Maybe track down my 5.9 ZJ and swap that beast over!!!

I'm sure all will work out. No matter what I've got my dream vehicle/future daddy mobile and damn happy!
 
#25 ·
Damn phone. Already typed this **** twice. Dropped my 12 off tonight for leak test. Techs hanging out afterwards. Said all of them CLICK & TICK. Sand in the motors. Have to tear apart and clean/flush. Must have been building the motors in Myrtle Beach.

Drive it til it pukes and swap in a 4bt or 6.4.

Cheers!
 
#28 ·
Remember on the net you can find problems with anything you want to. Some real some not. Don't worry about your 3.6. I do NOT know everything but I am the Parts Manager at Louisiana's largest volume Chrysler Dealership and I just bought a 2012 Crush Orange two door Jk. Sold my 4.0 2000 Lifted...........TJ. I love this thing and am not worried at all!!!!!! Let's JEEP!!!!!
 
#32 ·
Absolutely no noise from my PentaJesus.

Though I come from subaru's, all their motors tick.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top