5.9L powering off randomly - 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 > 5.9L powering off randomly

FS: Wranger BRIGHT License Plate LED! Just $3! Great valueThanksgiving/Black Friday/Cyber Monday Deals at JeepinOutfBlack Friday Sale!!

Reply
Unread 12-14-2007, 05:19 PM   #1
dundun
Registered User
 
Join Date: Nov 2007
Location: New York
Posts: 19
5.9L powering off randomly

A few months back I bought a Jeep 5.9L with 131,500 miles on it. Everything was fine, I put a new battery, battery cables, oil change, air filter, fill it with premium gas, etc... then when the mileage clock hit exactly 132,000 this morning the car is now powering off randomly.

Today it happened 3 times, once when I was turning into a parking lot I lost all power. I repeatedly turned the key, each time the engine turned on it would turn off after 2 seconds. I eventually got it to stay on by pumping the gas pedal while turning the key. Then it happened again when I was turning into a different parking lot (this time I was turning from a busy street, which is not fun to stall on). Once again I did my pump gas pedal trick and it worked.

So I figured somehow my turning the car while applying the brake was causing this to happen. WRONG. When I returned to my parked car and tried to reverse to get out of the parking lot, it powered off on me again. Pedal trick worked and after that last time it hasn't acted up so far.

Aside from the temperature rapidly changing (yesterday there was a snow storm, today 50% of the snow has melted) What could be the cause of this problem? Any help would be much appreciated, thanks.

dundun is offline   Reply With Quote Quick reply to this message
Unread 12-14-2007, 08:43 PM   #2
Vestjam
Senior Member
 
Vestjam's Avatar
2008 JK Wrangler 
 
Join Date: Feb 2006
Location: Illinois
Posts: 763
IF you can keep it running by just holding the gas pedal down a bit and it dies while idling (let off the gas), I'd say your throttle position sensor (TPS) is going bad.

Check your codes and see it the computer points you in the same direction.
__________________
2008 Jeep Wrangler X (Hard Top)
Incubus Off Road 511's with BFG 285/70-17

1998 Jeep Cherokee Sport
4.0L/AW4, Yakima Roof Rack
Vestjam is offline   Reply With Quote Quick reply to this message
Unread 12-16-2007, 01:38 AM   #3
Nurburgringer
Registered User
1998 ZJ 
 
Join Date: Nov 2007
Posts: 238
not exactly the same issue as yours, but the 5.9 w/ 142k I bought 3 weeks ago wouldn't start the day after I put on the Hughes Engines aluminum intake plenum plate (pics here http://s180.photobucket.com/albums/x...bach/Cherokee/)
Started and ran fine for the 2 hour drive home after that job, then the next morning just cranked without starting.

Left it sit while I was out of town last week, this morning started up but died shortly thereafter. Put on a new TPS ($30 Autozone) because the CPS I ordered from Rockauto wasn't in yet, not really expecting it solve much except for the 45-65 mpg RPM wandering. It did that, and also seems to run smoother.
Still I'm going to be a bit nervous turning the key for a while...
good luck and let us know what it was please!
Kurt
Philly
'98 5.9
Nurburgringer is offline   Reply With Quote Quick reply to this message
Unread 12-16-2007, 01:52 AM   #4
Colorado 5.9
Registered User
1998 ZJ 
 
Join Date: Dec 2001
Location: Denver, Colorado
Posts: 2,049
1: Crank Position Senser is about to die completely.

Mine did about the same thing way back about 70k.

I was lucky that it happened less than a block from the dealler. It was still under warranty.

I could start it but every time i put it into gear it would die. If I put it into reverse it would be OK.

If not that, it could be a flakey battery or fuel pump or like above the TPS.
__________________
ZJ 98 5.9 LTD. Lots of mods. 7" T&T's Long Arm Lift ,BFG KM2"s,35X12.50x16's,4:56's, Vanco brake upgrade, M1intake,Holley52mmTB,MikeLeach Headers,, Arb'ed HP D30,Aussie Locked rear,Procomp MX6 Shocks,Arb front,RearTR bumpers,ECT.ECT.

Latest Pics
Colorado 5.9 is offline   Reply With Quote Quick reply to this message
Unread 12-16-2007, 02:23 PM   #5
dundun
Registered User
 
Join Date: Nov 2007
Location: New York
Posts: 19
Last night I had a little more time testing the truck and i've figured a few things out:

1. The engine cranks, but does not fully start up unless I: turn key-gas pedal-brake pedal then quickly shift into reverse or drive and hit the gas to keep it alive.

2. a loud squealing sound comes from the engine when i'm trying to start it up, the security guard at my job has the same problem with his car and he believes its a belt.

3. The second I stop giving gas to the car, it begins to die. Stop lights are now my nemesis.

The loud squealing noise coming from the engine is definetly the cause of the stalling, what do you guys think it could be? thanks for any suggestions and advice.
dundun is offline   Reply With Quote Quick reply to this message
Unread 12-16-2007, 02:32 PM   #6
Colorado 5.9
Registered User
1998 ZJ 
 
Join Date: Dec 2001
Location: Denver, Colorado
Posts: 2,049
One of you pullies is seised. Check the idler pully first.

Then the belt tensioner pully. Those are the most likely.

Might even be the power steering one.
__________________
ZJ 98 5.9 LTD. Lots of mods. 7" T&T's Long Arm Lift ,BFG KM2"s,35X12.50x16's,4:56's, Vanco brake upgrade, M1intake,Holley52mmTB,MikeLeach Headers,, Arb'ed HP D30,Aussie Locked rear,Procomp MX6 Shocks,Arb front,RearTR bumpers,ECT.ECT.

Latest Pics
Colorado 5.9 is offline   Reply With Quote Quick reply to this message
Unread 12-16-2007, 05:10 PM   #7
Nurburgringer
Registered User
1998 ZJ 
 
Join Date: Nov 2007
Posts: 238
Quote:
Originally Posted by Colorado 5.9
1: Crank Position Senser is about to die completely.

Mine did about the same thing way back about 70k.

I was lucky that it happened less than a block from the dealler. It was still under warranty.
Damn - my 5.9 wouldn't start again today. Again I've got to leave town tonight, so took the CRX and left the BMW for the missus until I get back on Wednesday and have a crack at that CPS. At least the new plugs, wires, and dist cap from Hughes Engine (and a OEM coil to replace the MSB one since it looks like it was installed and wired by a 5 year old) should be in by then so I won't have to put the old ones back.

I've read in the Haynes book that the CPS is on the passenger side bank of the engine towards the rear, have to remove the exhaust manifold heat shield to get to. Anybody know what size socket/how many extensions/universals (if any) might be necessary to get to this? I'm working with limited tools where I'm currently at - Pop's stocked garage is 2 hours away...

cheers
Kurt
Nurburgringer is offline   Reply With Quote Quick reply to this message
Unread 12-16-2007, 05:14 PM   #8
Nurburgringer
Registered User
1998 ZJ 
 
Join Date: Nov 2007
Posts: 238
Quote:
Originally Posted by dundun
3. The second I stop giving gas to the car, it begins to die. Stop lights are now my nemesis.

The loud squealing noise coming from the engine is definetly the cause of the stalling, what do you guys think it could be? thanks for any suggestions and advice.
3. really sounds like a TPS, unless one of the accessories or idler pulley really is siezed. Easy to check - pop the belt off by leaning on the tensioner (1/2" box end wrench I think), then just check for free spinning of each pulley (except for crank of course).
First time I put on the new TPS I didn't index the female part correctly with the flat bit that rotates when throttle is engaged - so the computer didn't recognize I was pushing the throttle until about 1/3 of the way. Removed again (small torx head), indexed it correctly, then it ran (yesterday at least... today the CPS decided not to show up for work again...)
Kurt

oh yeah - and replace that belt. Might have damage from seized idler pulley.
Nurburgringer 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


Suggested Threads





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.