'97 ZJ Stalling - 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 > '97 ZJ Stalling

FS: Wrangler RGB Multicolor Fog Light LEDs: Awesome EffectSavvy Aluminum Gas Tank SkidFS: 2007-2013 Jeep Wrangler "HALO" Angel Eye Kit

Reply
Unread 09-02-2013, 01:28 AM   #1
phillipjohnw
Registered User
2000 TJ Wrangler 
 
Join Date: Sep 2013
Location: Honolulu, HI
Posts: 3
'97 ZJ Stalling

I have an automatic '97 ZJ that has had the problem everyone else seems to be having with the stalling issue. Every time it did stall out, it would start right back up without waiting more than a few seconds. Assuming that it was related to the PCM, my wife and I tried the backing out of the screws trick as well as just unplugging the PCM and making sure the connections were back in tight. These few things helped for a few months.

However, lately, the stalling issue has been getting progressively worse to the point that one minute it will be running just fine, and the next it just shuts off and won't get started back up for 10 minutes, if not longer, completely at random. Most of the time, it starts stalling out when the gas isn't being pushed. My wife has found out that if she throws the car in neutral, keeps her foot on the gas so it has around 2,000 RPM and easing into a stop that way, the car doesn't stall. Every time we got in the car, we didn't know if it'd drive fine or if it would stall out 2 miles down the road.

But all that changed yesterday as the car won't stay on longer than a few minutes before shutting off. Sometimes right away, sometimes grumbling a bit before it happens. I had to tow it home today after it wouldn't start along a highway. It was sitting overnight because she couldn't get it started after work yesterday. This is the second time we've had issues even getting the car started.

Other things it has been doing around the time it stalls out includes (all according to my wife):
- The noise that accompanies it sounds kind of like a diesel/semi truck where the pitch gets remarkably lower than a normal gasoline car before puttering out. She calls it a grumbling.
- The idling goes like it wants to stall, but then fluctuates like it might continue on as normal. Even if you stop the car, it still fluctuates like it's trying to stall, but still wants to stay on. It will do this for several minutes if the car isn't shut off. Even pushing the gas doesn't help try to start it 90% of the time.
- Sometimes while driving (no braking or anything), the car will act like it is about to stall, but taking your foot off the gas will help it continue on as normal, no problems.

We have changed the spark plugs, TSP, and fuel pump recently. The filter was fine when I did the fuel pump. My wife also says the exhaust noise sounds louder or different right after she starts it back up after it stalls.

Anyone had this happen before? Or have any ideas of what it could be?

phillipjohnw is offline   Reply With Quote
Unread 09-02-2013, 01:39 AM   #2
nodoze
Registered User
1996 ZJ 
 
Join Date: Jun 2013
Location: TC, Minnesota
Posts: 112
Have you checked for codes? If you do the key on, key off, key on three times in a row it will display codes on the dash where the odometer is.

Have you ever cleaned the idle control and throttle body?

Welcome to jeepforum
__________________
First Jeep, still a newb :)
1996 ZJ Laredo 4.0 w/ 242 SelecTrac
nodoze is offline   Reply With Quote
Unread 09-02-2013, 02:08 AM   #3
phillipjohnw
Registered User
2000 TJ Wrangler 
 
Join Date: Sep 2013
Location: Honolulu, HI
Posts: 3
Codes are 12, 14, 43. I don't think it's a fuel issue because I've noticed it still gets fuel even when doing this.
phillipjohnw is offline   Reply With Quote
Unread 09-02-2013, 04:35 AM   #4
nodoze
Registered User
1996 ZJ 
 
Join Date: Jun 2013
Location: TC, Minnesota
Posts: 112
Code 12 is for the battery being disconnected at some point and I don't think that's anything to be concerned about usually.
14 is for the MAP sensor and I think it would cause issues like you're having. You can try cleaning it, and checking for broken vacuum lines, and replacing the sensor if cleaning it doesn't help.
Code 43 copied from another post:
43 Peak primary coil current not achieved with max dwell time
OR
43 Cylinder misfire
OR
43 Problem in power module to logic module interface

I'm not sure about the 43, I'd start with the MAP sensor if it was mine. Hope this helps
__________________
First Jeep, still a newb :)
1996 ZJ Laredo 4.0 w/ 242 SelecTrac
nodoze is offline   Reply With Quote
Unread 09-02-2013, 07:09 AM   #5
JS97ZJ
Registered User
1997 ZJ 
 
Join Date: Dec 2009
Location: Dingmans Ferry, PA
Posts: 2,034
My advice is not to throw parts at this problem. Some after market parts are not all that good and most guys here will recommend using Mopar replacements that can get quite expensive.

It sounds like your having an intermittent problem with the PCM due to bad solder connections on the circuit board, but be advised other things can cause it. If it is the bad solder joints it can cause erroneous error code like your having along with others and can also give you back fires that can quickly take out you cat.

Look though ZeeJay's 12 things list and don't miss any steps. He links my repair procedure for fixing the PCM if that is the problem and I'm sure he'll pick up on your thread and find the solution.
Welcome to hell......

http://www.jeepforum.com/forum/f13/1...talls-1407423/
JS97ZJ is offline   Reply With Quote
Unread 09-02-2013, 01:33 PM   #6
Oldfrog
Web Wheeler
1997 ZJ 
 
Join Date: Feb 2008
Location: Louisiana/Texas
Posts: 3,825
Ditto on using Zeejay's list.
When you DO finally find the problem, please do others a favor and post it.
__________________
Cajun Recipes and Fishing tips

Words of wisdom, Posted by Zeejay:
"..it's not air, it is the opposite of air... suckage so to speak."

Stalling? Work through Zeejay's list
Oldfrog is offline   Reply With Quote
Unread 09-02-2013, 04:40 PM   #7
cletus93
Registered User
 
Join Date: Jun 2013
Posts: 4
Test your spark mine did the same thing and it ended up bein the coil pack
cletus93 is offline   Reply With Quote
Unread 09-02-2013, 07:41 PM   #8
ZeeJay1997
Registered User
1997 ZJ 
 
Join Date: Dec 2008
Location: Sweet Home, Alabama
Posts: 6,386
Quote:
Originally Posted by phillipjohnw View Post
I tried the backing out of the screws trick as well as just unplugging the PCM and making sure the connections were back in tight. These few things helped for a few months.
To me this is the most telling symptom. Dont think for a minute that moving those two screws did anything but rearranged some loose solder joints or connector sockets. So did reseating the connectors.

Try the zipties over the connectors and see if it improves. If it does, you need to repair or replace the PCM.

Once you get it running correctly, be sure the cat and muffler are clear. if your header is cracked, it probably been running rich and toasted the cat.
ZeeJay1997 is online now   Reply With Quote
Unread 09-06-2013, 02:52 AM   #9
Speedymcracer01
Registered User
 
Join Date: Feb 2013
Posts: 663
Quote:
Originally Posted by ZeeJay1997 View Post

To me this is the most telling symptom. Dont think for a minute that moving those two screws did anything but rearranged some loose solder joints or connector sockets. So did reseating the connectors.

Try the zipties over the connectors and see if it improves. If it does, you need to repair or replace the PCM.

Once you get it running correctly, be sure the cat and muffler are clear. if your header is cracked, it probably been running rich and toasted the cat.
My exhaust manifold was cracked for over a year didn't cause any real problems besides it being louder. That just caused it to adjust the air fuel mixter when it shouldn't have which just decreased my mpg. Seems like majority of the exhaust manifolds tend to crack in-between where the two pipes go into one before the thermal exhaust sensor
Speedymcracer01 is offline   Reply With Quote
Unread 09-06-2013, 05:20 AM   #10
ZeeJay1997
Registered User
1997 ZJ 
 
Join Date: Dec 2008
Location: Sweet Home, Alabama
Posts: 6,386
Quote:
Originally Posted by Speedymcracer01 View Post
My exhaust manifold was cracked for over a year didn't cause any real problems besides it being louder. That just caused it to adjust the air fuel mixter when it shouldn't have which just decreased my mpg. Seems like majority of the exhaust manifolds tend to crack in-between where the two pipes go into one before the thermal exhaust sensor
A richer mixture can cause early failure of the cat. it really all depends on the characteristics of the crack. Whether or not you had a problem is of no consequence. If you want to run a cracked manifold, go ahead.
ZeeJay1997 is online now   Reply With Quote
Unread 09-06-2013, 05:29 AM   #11
Speedymcracer01
Registered User
 
Join Date: Feb 2013
Posts: 663
Quote:
Originally Posted by ZeeJay1997 View Post

A richer mixture can cause early failure of the cat. it really all depends on the characteristics of the crack. Whether or not you had a problem is of no consequence. If you want to run a cracked manifold, go ahead.
Never said i wanted to run a cracked manifold i can't stand it. It sounds horrible and uses more gas. I was just saying it doesn't hurt much if you need time to get another manifold.i finally went and pulled one from the junk yard for mine,but it happened to be cracked around the same spot"where the two pipes go into one coming off the manifold"it just wasn't cracked as bad as mine was so i welded it and put it on till i can get a new, or used one that's in good shape
Speedymcracer01 is offline   Reply With Quote
Unread 09-14-2013, 02:18 PM   #12
phillipjohnw
Registered User
2000 TJ Wrangler 
 
Join Date: Sep 2013
Location: Honolulu, HI
Posts: 3
Sorry, Its been a while and I've been busy with work. Ordered a cheap MAP sensor off ebay since that was the codes it was consistently throwing. For $15 with shipping I figured it was worth it. If it fixed the problem great then I can get a actual mopar one later. If not I'm out $15 no biggie. Between the cheap sensor and taking the pcm out and putting it back in it seems to have fixed itself for now. Still looking into finding another pcm as I found out the one in it is not the original but a reman.
phillipjohnw is offline   Reply With Quote
Unread 09-14-2013, 03:22 PM   #13
ZeeJay1997
Registered User
1997 ZJ 
 
Join Date: Dec 2008
Location: Sweet Home, Alabama
Posts: 6,386
Quote:
Originally Posted by phillipjohnw View Post
Between the cheap sensor and taking the pcm out and putting it back in it seems to have fixed itself for now.
It seems like every time you mess with the PCM, it straightens up for a while. i would be looking feverishly for a PCM if i really needed the vehicle.
ZeeJay1997 is online now   Reply With Quote




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.