Go Back   Jeep Garage - Jeep Forum > Jeep Platform Discussion > Grand Cherokee - WJ > Troubleshooting/Problems

Join Jeep Garage Today
Reply
 
Thread Tools Display Modes
 
  #1  
Old 07-07-2013, 08:00 PM
Member
 
Join Date: Mar 2013
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 487
coulsonan is on a distinguished road
Jeep Stalling

My 99 Jeep Grand Cherokee is stalling out. If I'm standing still it just dies, but if I'm moving I can pump the gas and sometimes it will come back alive. Most times I have to slide off the road and continue to try to start the engine. This will take anywhere from 2-5 minutes, often longer. This started about a year ago happening 10 times in 10 months, and has escalated to every time I run the jeep for the last two weeks. What could be wrong?
__________________

__________________
Reply With Quote
  #2  
Old 07-07-2013, 08:26 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,641
Thanks: 9
Thanked 54 Times in 52 Posts
Rep Power: 525436
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: Jeep Stalling

Which engine? Is the preventive maintenance done in time (ignitor plugs, air filter etc)? Did you check for eventual fault codes set, using the key dance? (ignition switch off/on three times and leave in on at the third time. The odometer will show "DONE" when all ok, or any fault code.)
Does it run ok at higher rpm's? Could be a problem with the Idle Air Control stepper motor or a dirty/clogged idle air passage. Remove the IAC stepper motor and clean the plunjer (don't twist it, otherwise you could damage the anti rotation tabs) and the air canal.
__________________

__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
Monroe Reflex shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #3  
Old 07-07-2013, 09:51 PM
Member
 
Join Date: Mar 2013
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 487
coulsonan is on a distinguished road
Re: Jeep Stalling

4.7v8, and yes maintenance is done, key dance reads P 1296 and then done, yes, it seems to run better on higher rpms, will check the IAC in the morning
__________________
Reply With Quote
  #4  
Old 07-07-2013, 10:49 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,641
Thanks: 9
Thanked 54 Times in 52 Posts
Rep Power: 525436
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: Jeep Stalling

P1296 = No 5 Volts to MAP Sensor, Loss of a 5 volt feed to the MAP Sensor has been detected.
Eventhough cleaning of the IAC is a good thing once in a while, it most probably will not help in this case. There could be something wrong with the MAP sensor (intake Manifold Air Pressure sensor), or one of the wires is shaved through and makes contact to ground once in a while. The sensor is mounted on the front side of the intake manifold with two bolts. Check the connector for dirt/grease and the wires as far as possible for shaving or other damage.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
Monroe Reflex shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #5  
Old 07-08-2013, 04:16 PM
Member
 
Join Date: Mar 2013
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 487
coulsonan is on a distinguished road
Re: Jeep Stalling

I replaced the sensor a year ago, I tested the sensor and it's getting 5v, but it's not putting out 5v, and when I was trying read the output it wasn't consistent, it was fluxuating.
__________________
Reply With Quote
  #6  
Old 07-08-2013, 05:43 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,641
Thanks: 9
Thanked 54 Times in 52 Posts
Rep Power: 525436
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: Jeep Stalling

The input voltage is regulated by the PCM at 5 V, so that seems to be ok.
The output voltage depends on the barometric pressure (and because of this, on the altitude the jeep is at). At sea level the voltage should be around 4.6 V and this value goes down to 0.3 V at high altitude. A fluctuating value is not normal. Did you measure it with the engine running or off (and ignition in run)? When the input voltage is steady, then or the MAP sensor is faulty, or there is a problem with the wiring.
There is a splice in the wiring close to the #7 ignition coil, splice S107.
You could measure the continuity of the wiring to rule out any problems there.
Measure from MAP sensor connector slot 2 to the PCM connector C1 slot 4. (this is the sensor ground). There should be continuity and a steady indication when you wiggle a bit with the wiring.
Do the same from MAP sensor connector slot 1 to PCM connector C1 slot 27. This should also give continuity and a steady indication. When these measurements are ok, then most probably the MAP sensor is faulty again.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
Monroe Reflex shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #7  
Old 07-09-2013, 03:17 PM
Member
 
Join Date: Mar 2013
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 487
coulsonan is on a distinguished road
Re: Jeep Stalling

I apologize, I tested the wrong sensor, don't know what was in my head, but I did replace the sensor a year ago, on the correct sensor this time when the key is on and I ground my tester and test wire 1 it reads 5v and the same with wire 3, and when I put pos on wire 1 and neg on wire 3 I get nothing, what does that mean?
__________________
Reply With Quote
  #8  
Old 07-09-2013, 06:26 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,641
Thanks: 9
Thanked 54 Times in 52 Posts
Rep Power: 525436
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: Jeep Stalling

Slot 3 is the supply reference signal from the PCM, which should be 5 V= OK
Slot 1 is the output signal from the MAP sensor and should be slightly lower then the supply power at sealevel or a lot lower at higher altitude.
If you get exact the same voltage at point 1 as at point 3, then there is ofcourse no differential between those points and you will measure 0 V.
That the supply voltage is the same as the output signal, that is strange. Did you already measure in ohms range between slot 2 from the MAP sensor and slot 4 from PCM connector C1 (both connectors disconnected)? There should be no or a very low resistance.
The fact that input voltage and output voltage are the same, does me make believe that there is a problem with the sensor ground. This sensor ground doesn't necessarely have to be connected directly to chassis ground, it goes into the PCM. As told before, there is a splice in this ground wire close to ignitor coil #7 (left aft cylinder as seen from drivers position). So when you check the continuity of the sensor ground wire, wiggle a bit with the wire bundle, especially close to the ignitor #7, and see if it is steady or fluctuating or maybe even open.
__________________

__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
Monroe Reflex shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
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
2000 Jeep Grand Cherokee Stalling dr300yards Troubleshooting/Problems Discussion 1 06-13-2013 01:44 AM
2006 jeep cherokee limited 4.7 still stalling chris2006cherokee Troubleshooting/Problems 7 03-14-2013 06:25 PM
Stalling? BigChris Troubleshooting/Problems 1 01-18-2013 10:08 AM
Rattling and stalling whilst driving my jeep Ward Export & Diesel Powered Jeep Models 7 11-29-2011 06:08 AM
Brake Stalling Robert Palmer At The Track 10 06-27-2009 09:24 PM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 05:44 AM.


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