Go Back   Jeep Garage - Jeep Forum > Jeep Platform Discussion > Grand Cherokee - WK2 -

Join Jeep Garage Today
Reply
 
Thread Tools Display Modes
 
  #13  
Old 08-14-2012, 07:35 AM
padgett's Avatar
Premium Member
 
Join Date: Feb 2012
Location: Orlando
Posts: 1,568
Thanks: 0
Thanked 24 Times in 21 Posts
Rep Power: 80278
padgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond repute
Re: Pentastar head problem reported on autoweek.

"Cheap gas"> lower octane> detonation when hot> not detecting detonation in #2> burned valves.

Yet another reason to run the engine 10% cooler.

Wonder if more common in mountain states where regular may be 85 octane.

Thinking a bit more: the specific drive cycle might be slow speed/moderate load/high engine temp (high load kicks in PE/richer mixture). Easy fix if has not happened, back off the thermostat (185F), bring in fans sooner (195F), increase knock sensor sensitivity, (optional) richen #2 a touch when coolant is above 200F. All but first are just flashes so very low cost. Thermostat is slightly more say $5 part/ .5hr labor.

or just advise to use 89 octane when rock climbing or trailer towing on a hot day.

Would explain why is being seen more in Wranglers if a major factor is how they are driven.
__________________

Reply With Quote
  #14  
Old 08-15-2012, 05:39 AM
Member
My Jeep: 2012 3.6L WK2
 
Join Date: Feb 2012
Posts: 305
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 1357
tnjeep has disabled reputation
Re: Pentastar head problem reported on autoweek.

What I don't like is that if this "unusual mix of circumstances" happens you will get your engine fixed under warranty but if you are a mile over or a day over the 5/100K warranty and this mix happens you are screwed. IMO they should fix all the engines but I got time to see how many engines are going to be affected before trading.
__________________

__________________
Reply With Quote
  #15  
Old 08-15-2012, 08:20 AM
Member
My Jeep: 2011 3.6L WK2
 
Join Date: May 2011
Location: Massachusetts
Posts: 305
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1625
hammer1234 is on a distinguished road
Re: Pentastar head problem reported on autoweek.

Quote:
Originally Posted by tnjeep View Post
What I don't like is that if this "unusual mix of circumstances" happens you will get your engine fixed under warranty but if you are a mile over or a day over the 5/100K warranty and this mix happens you are screwed. IMO they should fix all the engines but I got time to see how many engines are going to be affected before trading.
I can't see Chrysler fixing all engines but there should be an extended warranty for this problem (say 8-10 years and unlimited miles). I had an 8 year warranty on my 2001 Toyota Highlander V6 for potential oil sludge problems which I was able to stave off by being good about oil changes. Car has some oil consumption issues now but the engine is just under 200K so while it could be sludge it could just be wear.

http://www.consumeraffairs.com/news0...ettlement.html
__________________
Reply With Quote
  #16  
Old 08-15-2012, 08:44 AM
padgett's Avatar
Premium Member
 
Join Date: Feb 2012
Location: Orlando
Posts: 1,568
Thanks: 0
Thanked 24 Times in 21 Posts
Rep Power: 80278
padgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond repute
Re: Pentastar head problem reported on autoweek.

Can bet that even if a recall is ordered, it won't be to replace heads, back in 85ish when the Fiero recall was ordered, the general added a splash shield, changed the oil filter, and remarked the dipstick.

Today the best to hope for is a new cooler thermostat but suspect the "fix" will all be computer programming.

It does seem odd that with two knock sensors they are not picking up detonation unless that is included in "misfire".

Suspect there are a lot of dyno hours being put in to determine the exact conditions but supect a major one would be to just run the engine a little bit cooler (like 10F coolant) which has a lot of side benefits.

Detonation (knock) is a funny thing. An SI engine runs best when right on the edge. Back in the day we used to "tune" for max power by advancing the distributer until you could just hear "ping" under load, then back off 2 degrees.

This is why it rarely helps and often hurts today to run premium gas (which needs more advance) with a computer designed for 87 PON (burns faster), the advance maps do not go far enough.

Have gone into a long dissertaion on PON and advance before, is not a simple subject. Won't. Just keep in mind that the SI (or CI for that matter) engine is a complex kludge designed for one thing: peak chamber pressure at 5-15 degrees (varies by engine) ATDC. Too much advance and you get detonation, too much advance with a lean mixture and Things Burn (like valves).

Until we know the cause and why it is necessary to replace a head when it occurs instead of just valves and possibly valve guides (casting defect maybe ?) we are really just guessing. All I can say is that nearing 4k miles, mine is running perfectly and has used no oil (burning oil might be an indicator).
Reply With Quote
The Following User Says Thank You to padgett For This Useful Post:
  #17  
Old 08-15-2012, 08:12 PM
Member
My Jeep: 2011 3.6L
 
Join Date: Aug 2012
Location: AL
Posts: 20
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 884
11Durango is on a distinguished road
Re: Pentastar head problem reported on autoweek.

Hi All,

My 2011 Durango (new to me as of 8/1/12) I bought used with 37k miles is scheduled to go in for left head replacement next Monday.

Threw P0302 Code according to my Scangauge. No ticking or other symptoms, just the engine light.

I actually went into the dealer armed with everything I've read on this Pentastar issue a couple weeks ago. Dropped the D in and dealer called next day confirming needs new head. Head ready to go in as of this Monday, but will have to wait until next Monday as I'm out of town for the week. Also, they are replacing the head with a remanufactured one according to the dealer.

Build date on door is 5/2011. Don't have original window sticker, so not sure if engine was made in Mexico or US? Thank goodness for the transferrable 5yr/100k powetrain warranty! I will post with update after repair.

Other than this, still lovin the Durango!
__________________
Reply With Quote
  #18  
Old 08-15-2012, 09:18 PM
ajs800's Avatar
Member
My Jeep: 2011 3.6L WK2
 
Join Date: Jun 2011
Location: Michigan
Posts: 744
Thanks: 0
Thanked 5 Times in 5 Posts
Rep Power: 32131
ajs800 has a reputation beyond reputeajs800 has a reputation beyond reputeajs800 has a reputation beyond reputeajs800 has a reputation beyond reputeajs800 has a reputation beyond reputeajs800 has a reputation beyond reputeajs800 has a reputation beyond reputeajs800 has a reputation beyond reputeajs800 has a reputation beyond reputeajs800 has a reputation beyond reputeajs800 has a reputation beyond repute
Re: Pentastar head problem reported on autoweek.

mine goes in tomorrow for either a camshaft sensor issue or maybe this head issue. it's the second time going in for the same camshaft issue which could very well be this problem.
__________________
2011 Overland, Dk Charcoal Pearl, Black/Saddle w/Summit Wood Trim Swap, V6, QL, 20" wheels, 730N
Reply With Quote
  #19  
Old 08-15-2012, 11:07 PM
padgett's Avatar
Premium Member
 
Join Date: Feb 2012
Location: Orlando
Posts: 1,568
Thanks: 0
Thanked 24 Times in 21 Posts
Rep Power: 80278
padgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond reputepadgett has a reputation beyond repute
Re: Pentastar head problem reported on autoweek.

Makes sense, P0302 is "Cylinder #2 Misfire Detected". If a cam or crank sensor would expect more than one cyl to be out. Wonder if the "remanufactured" head had a intake ported on #2.

BTW that one seems to result from an RPM change detected by the computer and not a knock sensor (YMMV)

Be interesting to see the factory instruction sheet on replacing the cyl head if anything is modified or something (like the foam isulator on top of the valve cover behind the oil filler tube) is left off.
Reply With Quote
  #20  
Old 08-16-2012, 07:10 AM
Member
My Jeep: 2012 3.6L WK2
 
Join Date: Sep 2011
Location: Cherry Valley, IL
Posts: 345
Thanks: 0
Thanked 7 Times in 5 Posts
Rep Power: 4673
brandont has a reputation beyond reputebrandont has a reputation beyond reputebrandont has a reputation beyond reputebrandont has a reputation beyond reputebrandont has a reputation beyond reputebrandont has a reputation beyond reputebrandont has a reputation beyond reputebrandont has a reputation beyond reputebrandont has a reputation beyond reputebrandont has a reputation beyond reputebrandont has a reputation beyond repute
Re: Pentastar head problem reported on autoweek.

Quote:
Originally Posted by tnjeep View Post
What I don't like is that if this "unusual mix of circumstances" happens you will get your engine fixed under warranty but if you are a mile over or a day over the 5/100K warranty and this mix happens you are screwed. IMO they should fix all the engines but I got time to see how many engines are going to be affected before trading.
Agreed. They are saying that only a low percentage of engines are effected, which makes it sound like only those engines are defective - but that isn't true. All the built V6 to date have the defect, it is just that most of us don't notice it because of our conditions. It doesn't mean the next owner won't have a problem. Or that if you move, decide to buy a boat, or change your commute that your engine won't develop a problem. Just because the current owner and circumstances didn't break something does not mean the problem shouldn't be addressed. Are they going to compensate me for lost resale value because the next owner doesn't want my non-fixed V6? Sorry, but Chrysler needs to make it right for everyone.
__________________
Reply With Quote
  #21  
Old 08-16-2012, 08:15 AM
Member
My Jeep: 2011 3.6L WK2
 
Join Date: Oct 2011
Location: Kentucky
Posts: 98
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 1274
americanbulldog is on a distinguished road
Re: Pentastar head problem reported on autoweek.

Quote:
Originally Posted by brandont View Post
Agreed. They are saying that only a low percentage of engines are effected, which makes it sound like only those engines are defective - but that isn't true. All the built V6 to date have the defect, it is just that most of us don't notice it because of our conditions. It doesn't mean the next owner won't have a problem. Or that if you move, decide to buy a boat, or change your commute that your engine won't develop a problem. Just because the current owner and circumstances didn't break something does not mean the problem shouldn't be addressed. Are they going to compensate me for lost resale value because the next owner doesn't want my non-fixed V6? Sorry, but Chrysler needs to make it right for everyone.
Totally agree, this will affect resale value, there needs to be a recall, especially since our taxes kept Chrysler afloat, and we also supported the company by buying their product. I know one thing, I'm not near as happy with this vehicle as I was a few days ago, if the check engine light does come on, will stop and tow.
__________________
Reply With Quote
  #22  
Old 08-16-2012, 10:06 AM
Member
My Jeep: 2011 3.6L WK2
 
Join Date: May 2011
Location: Massachusetts
Posts: 305
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1625
hammer1234 is on a distinguished road
Re: Pentastar head problem reported on autoweek.

Quote:
Originally Posted by americanbulldog View Post
Totally agree, this will affect resale value, there needs to be a recall, especially since our taxes kept Chrysler afloat, and we also supported the company by buying their product.
When was the last time that a recall was done for a non-safety defect?

I'm not saying that Chrysler shouldn't fix defective engines, it's just that if they had to implement a mass recall we'd never be able to get our vehicles into a dealer for service because they would be spending all of their time replacing Pentastar heads.

I'd be happy with a very extended (lifetime or close) warranty that includes a free rental and then just drive and hope I don't see the problem.
__________________
Reply With Quote
  #23  
Old 08-16-2012, 02:00 PM
Premium Member
My Jeep: 2014 3.6L WK2
 
Join Date: Aug 2010
Location: Puyallup
Posts: 59
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1632
Daved51 is on a distinguished road
Re: Pentastar head problem reported on autoweek.

I have a '11 v6 with 40k and had the head replaced under warrenty. With ~1500 miles on the new head we are heading from the Pacific Northwest to each coast for 3 weeks.
__________________
Current: 2014 Overland V6 -Bilit Silver , ORII, ACC (Delv 4/3/14)
Trade: 2011 Overland V6 ORII - Dark Charcoal Pearl
Trade: 1994 GC Limited V8
Trade: 1984 Cherokee Chief - l4 TD
Reply With Quote
  #24  
Old 08-16-2012, 02:17 PM
Premium Member
 
Join Date: Sep 2010
Location: brOOklyn
Posts: 1,258
Thanks: 0
Thanked 3 Times in 3 Posts
Rep Power: 2853
JoeSchmoe007 has a reputation beyond reputeJoeSchmoe007 has a reputation beyond repute
Re: Pentastar head problem reported on autoweek.

Am I correct that there was no official announcement from Chrysler on nature of the problem, cars affected and fix? Can someone with more technical knowledge speculate what the problem is and why head replacement fixes it? Was design for engine head changed?
__________________

__________________
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
BEST large SUV award-2 years in a row-autoweek! Scottina06 2011+ Dodge Durango-WD 0 02-08-2012 07:41 PM
Pentastar Poncho Wrangler-YJ, TJ & JK 2 01-16-2012 08:11 AM
3.6 Pentastar TB FlyinRyan Flyin' Ryan Performance 2 01-13-2012 10:58 PM
new 3.6l pentastar jakeda Suspension/Driveline/Brakes/Wheels/Tires 12 12-13-2011 09:09 PM
Jeep WK1 SRT8 vs 2012 WK2 vid head to head drag oldgeezer Grand Cherokee SRT8 - WK 0 12-08-2011 07:12 PM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 11:41 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community

JeepGarage.org is in no way associated with or endorsed by Chrysler Group LLC.