5.9 pcm - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Grand Cherokee & Commander Forums > ZJ Grand Cherokee Forum > 5.9 pcm

Rampage Bowless Soft Top Oconee offroadAlloy USA Still AvailableAdvance Adapters SYE Kits

Reply
Unread 02-01-2013, 05:42 PM   #1
MN59ZJ
Registered User
1998 ZJ 
 
Join Date: Apr 2010
Location: Lakeville, MN
Posts: 557
5.9 pcm

I'm having an issue that may be caused the PCM in my 5.9 ZJ. I'm simply wondering if I can yank the PCM from a 5.9 Durango or Dodge pickup at the u-pull lot & swap it into the ZJ to see if that solves my problem?

MN59ZJ is offline   Reply With Quote Quick reply to this message
Unread 02-01-2013, 05:48 PM   #2
T-nave
Registered User
1998 ZJ 
 
Join Date: Jan 2012
Location: Grand Ledge, MI
Posts: 216
I could be wrong on this but I believe the 5.9 is programmed differently. It may work but your not going to get the same performance. Now would be a good time to get a custom tuned pcm. The person that programs it may be able to check/fix problems with yours.
__________________
9er, 3.5 IRO lift + 3/4" spacers w/ adjustable trac bars and arms, 242 swap, 285/70/17 Duratracs and some other doo dads
T-nave is offline   Reply With Quote Quick reply to this message
Unread 02-01-2013, 06:01 PM   #3
MN59ZJ
Registered User
1998 ZJ 
 
Join Date: Apr 2010
Location: Lakeville, MN
Posts: 557
Quote:
Originally Posted by T-nave
I could be wrong on this but I believe the 5.9 is programmed differently. It may work but your not going to get the same performance. Now would be a good time to get a custom tuned pcm. The person that programs it may be able to check/fix problems with yours.
It's a LONG story, but I have an SCT tuner & a recently rebuilt (& improved ;-) ) engine. The problem I'm having is likely either caused by a bad PCM, or an error with the tuner. As I've chased every other possibility down with no success. For now, I just want to pop in another PCM & see if the issue goes away.
MN59ZJ is offline   Reply With Quote Quick reply to this message
Unread 02-01-2013, 06:20 PM   #4
T-nave
Registered User
1998 ZJ 
 
Join Date: Jan 2012
Location: Grand Ledge, MI
Posts: 216
Cant you default back to original settings of your pcm? Then unhook your tuner?
__________________
9er, 3.5 IRO lift + 3/4" spacers w/ adjustable trac bars and arms, 242 swap, 285/70/17 Duratracs and some other doo dads
T-nave is offline   Reply With Quote Quick reply to this message
Unread 02-01-2013, 06:28 PM   #5
MN59ZJ
Registered User
1998 ZJ 
 
Join Date: Apr 2010
Location: Lakeville, MN
Posts: 557
Quote:
Originally Posted by T-nave
Cant you default back to original settings of your pcm? Then unhook your tuner?
I have. The code pops up in stock mode too, which indicates the PCM, but the problem didn't occur until I started using the tuner, which seems odd, but might be a coincidence. I can get a Dodge 5.9 PCM for $18. so if I can throw that in & see what happens, I can either confirm or eliminate the PCM as the problem & go from there... That is if the Dodge unit will work for this purpose.
MN59ZJ is offline   Reply With Quote Quick reply to this message
Unread 02-01-2013, 08:04 PM   #6
newfieZJ
Registered User
1995 ZJ 
 
Join Date: May 2008
Location: , Alberta
Posts: 6,483
For 18 bucks , no harm trying . What code ?
newfieZJ is offline   Reply With Quote Quick reply to this message
Unread 02-01-2013, 08:24 PM   #7
MN59ZJ
Registered User
1998 ZJ 
 
Join Date: Apr 2010
Location: Lakeville, MN
Posts: 557
Quote:
Originally Posted by newfieZJ
For 18 bucks , no harm trying . What code ?
Depends. The SCT. Has a built-in reader & gives P0140, but the Eqquis at O'Reilly's gives P0172. They are actually similar results, involving O2 sensors detecting a rich mix. Once I reset it, it runs fine on the next start up, I could drive til the tank is empty & it won't pop a code. But once I shut down, the next time I start it up, I get the code after 3-4 minutes, then it runs rich until I reset it.

It gets more complicated than that, but That's it in a nut shell.
MN59ZJ is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools






Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.