2000 Jeep Grand Cherokee 4.7 Engine stalling

PeterD wrote:
> On Wed, 2 Jun 2010 21:30:50 -0500, "James" <no >
> wrote:
>
>> Since I first posted this problem, I installed the CPS , about a
>> month ago. So, for a full month, I have had NO problem. But today,
>> at slow speeds of 20-30 mph, the engine shut down completely.
>> Then, the starter would turn over and over, but the engine would
>> not crank. All gauges remained at zero.
>
> Sounds like an ignition switch problem...
>
>> After some time, and turning the ignition on and off, the gauges
>> went back to
>> normal, and the engine started right up. I am not a mechanic, but
>> it seems to
>> me that this HAS to be an electrical problem.
>
> Probably, given the gauge problems...
>
>>
>> Yes, I will have a mechanic do the ODC codes asap, but what kind of
>> things are left, that I should be looking for ??
>>
>
> Check the connections/plugs to the PCM.

Also check up under the steering shaft where the ignition switch connector
plugs into the body connector.


--
DougW

good idea Doug. will pass this along to my mechanic tomorrow.....

James

On Tue, 15 Jun 2010 20:09:18 -0400, "James" >
wrote:

>I wanted to give an update on this ongoing saga. I took the Jeep to a
>Jeep dealer, and left it there for two days. While at the dealer, it ran
>fine. They claimed to have driven it some, and they claimed to have let it
>run at idle for hours at a time, then switch it off and on, etc etc. To
>make a long story short, they just told me that they could not duplicate the
>problem, and could not actually diagnose it. ...

That lack of gauges at all (including fuel for example) is a clear
indication that the computer is not working or communicating with the
outside world or the dash. All the gauges are 'buffered' through the
computer, which is why.

The inablity to diagnose is basically because they (the dealer) is
unable or unwilling to check hundreds of connectors, wires, and
electrical components to find where the problem lies. No surprise,
really, as it could take many hours.

Heat related? Probably, but the heat may be very localized--such as a
single pin on a connector, or a single wire to a pin, or even a fuse.

Suggestions:

1. Disconnect the battery before doing any of these, and wait ten
minutes before doing any of these.

2. Reseat all fuses. All of them!

3. Reseat all relays. Again, all of them, don't try to guess which one
might be a problem. Don't say--this is the xyz relay so it can't be
guilty: do it anyway.

4. Reseat all connectors, paying particular attention to connectors to
the ECM and other computer modules, connectors to fuse panels,
connectors to dash, and connectors under the dash. Reseat as many
connectors as you can find. When you unplug each connector,
*carefully* inspect the connector for discolored or damaged pins or
sockets, discolored wires emerging from the connector, etc.

5. Make sure your ground straps are all good, and tight.

PeterD wrote:

> On Tue, 15 Jun 2010 20:09:18 -0400, "James" >
> wrote:
>
>>I wanted to give an update on this ongoing saga. I took the Jeep to a
>>Jeep dealer, and left it there for two days. While at the dealer, it ran
>>fine. They claimed to have driven it some, and they claimed to have let
>>it
>>run at idle for hours at a time, then switch it off and on, etc etc. To
>>make a long story short, they just told me that they could not duplicate
>>the problem, and could not actually diagnose it. ...
>
> That lack of gauges at all (including fuel for example) is a clear
> indication that the computer is not working or communicating with the
> outside world or the dash. All the gauges are 'buffered' through the
> computer, which is why.
>
> The inablity to diagnose is basically because they (the dealer) is
> unable or unwilling to check hundreds of connectors, wires, and
> electrical components to find where the problem lies. No surprise,
> really, as it could take many hours.
>
> Heat related? Probably, but the heat may be very localized--such as a
> single pin on a connector, or a single wire to a pin, or even a fuse.
>
> Suggestions:
>
> 1. Disconnect the battery before doing any of these, and wait ten
> minutes before doing any of these.
>
> 2. Reseat all fuses. All of them!
>
> 3. Reseat all relays. Again, all of them, don't try to guess which one
> might be a problem. Don't say--this is the xyz relay so it can't be
> guilty: do it anyway.
>
> 4. Reseat all connectors, paying particular attention to connectors to
> the ECM and other computer modules, connectors to fuse panels,
> connectors to dash, and connectors under the dash. Reseat as many
> connectors as you can find. When you unplug each connector,
> *carefully* inspect the connector for discolored or damaged pins or
> sockets, discolored wires emerging from the connector, etc.
>
> 5. Make sure your ground straps are all good, and tight.

Good map, Peter. Couple of refinements to consider as you do them.

a. look for any sign of corrosion or tarnish on the connectors. I know it
smells, but my old MJ gets cranky after trips down to the Texas coast and I
finally quit being picky and just pull every fuse, spray the fuse block and
fuse pins with WD40 then run them in and out a few times. Blow the WD40
out as a last step or it will collect dirt and crud over time but it's a
quick and dirty that works.

b. if you see ANY sign of corrosion (greenish crud on a metal wire or pin)
soak the connector with contact cleaner (WD40 works but you have to blow it
dry) then try and work the connection to get mechanical cleaning. On older
Jeeps the fuse block was located on the firewall (under the dash) where any
leak from the brake or clutch cylinders would run down on it. The brake
fluid is hygroscopic and essentially pulls moisture inside the crimped
connections. I've had apparently solid, clean crimped connections go open
from the resulting corrosion inside the insulation and crimp.

The computer signals are low voltage/current so ANY amount of
tarnish/corrosion on contacts can result in erratic connections. Your
description tells me that you almost certainly have a connector problem.
And don't forget those ground points - Jeeps are notorious for losing
grounds at those points.

--
Will Honea

James wrote:

> I then took the Jeep to another private mechanic who has a good
> reputation, and I reviewed all the the facts with him. Â* Â*He is willing to
> invest some hours in testing grounds, etc etc, but he recommended one
> first step before I pay for a full day of diagnostic work. Â* Although I
> replaced the CPS in April, he indicates that he has installed a number of
> CPS units that turned out to be defective. Â* Â* He suggests that he first
> install another new CPS, and also replace the Â*Camshaft Position Sensor as
> well. Â* Then, we would go from there. Â* This guy is very reputable, and I
> truly believe he is trying to approach this from the most cost-effective
> approach.....
>
> Any further comments, based on this new info ?? Â* Â*If I have him replace
> those sensors, would you also replace the engine speed sensor Â*(code
> P0725) ??

Having fought CPS problems with the I6 more than a few times, I can tell you
that neither that of those sensors will shut the computer down to the point
of killing the gauges. The CPS will cause random shutdowns of the engine
and it can be heat sensitive. On GM products, the ECM was the most common
culprit - also heat related. I've had the most grief with cheap
replacement parts and the best luck using OEM parts for those functions.

--
Will Honea

bllsht wrote:

> First, the crank sensor IS the engine speed sensor to the TCM.
>
> Your "reputable" guy wants to start by throwing parts at it first?
> Before he checks anything? Before he even tries to duplicate the
> problem? Â*No guarantee it'll fix your problem either? Just sounds like
> the cheapest "guess" so far if you ask me. Â*That may translate to
> reputable to you, but...

Best comment yet! If you can't find, how you gonna "fix" it?

--
Will Honea

On Friday, April 23, 2010 12:37:45 AM UTC+1, James wrote:
> I have a 2000 Jeep Grand Cherokee, 4.7 liter engine. 205,000 miles.
> Engine has been literally perfect until last six months or so.
>
> In the last week, engine has stalled three times, at very slow idle, or very
> low speed. I have NO problems starting the engine. Today, while
> traveling
> on the interstate at 70 mph, my engine shuts off entirely, and all of my
> gauges
> go down to zero. It was as though some one unhooked the battery and the
> alternator at the same time. I allowed the car to slow down to about 50
> mph
> and all of a sudden, the gauges snap back into "normal" positions, and the
> engine resumes
> normal running, and I drive 300 more miles home without mishap, except that
> it again stalled twice at very low idle speeds (at red lights).
>
> Other than these rather serious quirks, I have good engine performance. No
> noises, etc.
> I am not a mechanic, but I would have suspected a fuel delivery problem
> were it not for
> the fact that my gauges went dead, which makes me wonder about the computer
> module
> or something like that. I have done the ignition switch on and off three
> times in sequence, but I get no error code. Just reads "done" after the
> third switch. I hope to get an OBD done asap.
>
>
> Within past six months I had some slow idle stalling and slow cranking
> problems. Based
> on advice here, I had the throttle body cleaned and the iac cleaned out.
> That took care of those
> problems at the time. Again, no problems starting now, just slow idle
> stalling, and the very weird engine and gauge shutdown at 70 mph (occurred
> once).
>
>
> Any commnents or advice will be appreciated. What should I be checking ?
>
> James

i own a 2000 grand cherokee just bought it with 122222 miles on it,it drives well but the engine keeps stalling at approx intervals of say 20mins and will not start untill about 3 to 4 hours i had it scanned and i have this errors P1391,P0100,P0181,P0725 pls which of these DTC will be responsible for the engine to be stalling.

ejikoseunwrote:
> On Friday, April 23, 2010 12:37:45 AM UTC+1, James wrote:
>> I have a 2000 Jeep Grand Cherokee, 4.7 liter engine. 205,000 miles.
>> Engine has been literally perfect until last six months or so.
>>
>> In the last week, engine has stalled three times, at very slow idle,
>> or very low speed. I have NO problems starting the engine.
>> Today, while traveling
>> on the interstate at 70 mph, my engine shuts off entirely, and all
>> of my gauges
>> go down to zero. It was as though some one unhooked the battery and
>> the alternator at the same time. I allowed the car to slow down to
>> about 50 mph
>> and all of a sudden, the gauges snap back into "normal" positions,
>> and the engine resumes
>> normal running, and I drive 300 more miles home without mishap,
>> except that it again stalled twice at very low idle speeds (at red
>> lights).
>>
>> Other than these rather serious quirks, I have good engine
>> performance. No noises, etc.
>> I am not a mechanic, but I would have suspected a fuel delivery
>> problem were it not for
>> the fact that my gauges went dead, which makes me wonder about the
>> computer module
>> or something like that. I have done the ignition switch on and off
>> three times in sequence, but I get no error code. Just reads
>> "done" after the third switch. I hope to get an OBD done asap.
>>
>>
>> Within past six months I had some slow idle stalling and slow
>> cranking problems. Based
>> on advice here, I had the throttle body cleaned and the iac cleaned
>> out. That took care of those
>> problems at the time. Again, no problems starting now, just slow
>> idle stalling, and the very weird engine and gauge shutdown at 70
>> mph (occurred once).
>>
>>
>> Any commnents or advice will be appreciated. What should I be
>> checking ?

Stalls at low speed are usually spark or timing related.
Sags at high speed are usually fuel delivery issues.

The crankshaft position sensor will kill your vehicle at low speed
and is temermental, meaning once your heep shuts off it might restart
again. CPS sensor faults are "sometimes" stored.

The other alternative is simply a bad battery. You can have a
cell break or a bad connector causing a temporary loss of power.
I literally pulled the terminal off my battery one time while
disconnecting it in order to check sensors. :/

The way you know it's a battery is you either have a HUGE number
of faults thrown or just the code for battery disconnected and no
others. The real tell, however, is when the damn thing falls
apart in your hand.

> i own a 2000 grand cherokee just bought it with 122222 miles on it,it
> drives well but the engine keeps stalling at approx intervals of say
> 20mins and will not start untill about 3 to 4 hours i had it scanned
> and i have this errors P1391,P0100,P0181,P0725 pls which of these DTC
> will be responsible for the engine to be stalling.


http://www.wjjeeps.com/faultcodes.htm

P1391 Loss of the Cam Position Sensor or Crank Position sensor has occurred.

This will cause the other errors as your engine hunts for timing.


--
-- DougW -- 93 ZJ 4.0 http://revbeergoggles.com
HESCO Supercharger - 300W IASCA Stereo - Edelbrock IAS Shocks
Gibson Exhaust - rear DCpower - custom gauge install - Stillen Rotors
Banks Header - and BEER, in the fridge!

On Thursday, September 6, 2012 11:06:35 PM UTC+1, DougW wrote:
> ejikoseunwrote: > On Friday, April 23, 2010 12:37:45 AM UTC+1, James wrote: >> I have a 2000 Jeep Grand Cherokee, 4.7 liter engine. 205,000 miles. >> Engine has been literally perfect until last six months or so. >> >> In the last week, engine has stalled three times, at very slow idle, >> or very low speed. I have NO problems starting the engine. >> Today, while traveling >> on the interstate at 70 mph, my engine shuts off entirely, and all >> of my gauges >> go down to zero. It was as though some one unhooked the battery and >> the alternator at the same time. I allowed the car to slow down to >> about 50 mph >> and all of a sudden, the gauges snap back into "normal" positions, >> and the engine resumes >> normal running, and I drive 300 more miles home without mishap, >> except that it again stalled twice at very low idle speeds (at red >> lights). >> >> Other than these rather serious quirks, I have good engine >> performance. No noises, etc. >> I am not a mechanic, but I would have suspected a fuel delivery >> problem were it not for >> the fact that my gauges went dead, which makes me wonder about the >> computer module >> or something like that. I have done the ignition switch on and off >> three times in sequence, but I get no error code. Just reads >> "done" after the third switch. I hope to get an OBD done asap. >> >> >> Within past six months I had some slow idle stalling and slow >> cranking problems. Based >> on advice here, I had the throttle body cleaned and the iac cleaned >> out. That took care of those >> problems at the time. Again, no problems starting now, just slow >> idle stalling, and the very weird engine and gauge shutdown at 70 >> mph (occurred once). >> >> >> Any commnents or advice will be appreciated. What should I be >> checking ? Stalls at low speed are usually spark or timing related. Sags at high speed are usually fuel delivery issues. The crankshaft position sensor will kill your vehicle at low speed and is temermental, meaning once your heep shuts off it might restart again. CPS sensor faults are "sometimes" stored. The other alternative is simply a bad battery. You can have a cell break or a bad connector causing a temporary loss of power. I literally pulled the terminal off my battery one time while disconnecting it in order to check sensors. :/ The way you know it's a battery is you either have a HUGE number of faults thrown or just the code for battery disconnected and no others. The real tell, however, is when the damn thing falls apart in your hand. > i own a 2000 grand cherokee just bought it with 122222 miles on it,it > drives well but the engine keeps stalling at approx intervals of say > 20mins and will not start untill about 3 to 4 hours i had it scanned > and i have this errors P1391,P0100,P0181,P0725 pls which of these DTC > will be responsible for the engine to be stalling. http://www.wjjeeps.com/faultcodes.htm P1391 Loss of the Cam Position Sensor or Crank Position sensor has occurred. This will cause the other errors as your engine hunts for timing. -- -- DougW -- 93 ZJ 4.0 http://revbeergoggles.com HESCO Supercharger - 300W IASCA Stereo - Edelbrock IAS Shocks Gibson Exhaust - rear DCpower - custom gauge install - Stillen Rotors Banks Header - and BEER, in the fridge!

thanks bro i checked through the battery connectors and i did not see anny issue but i removed the connectors to the plugs since u said it shld be spark related i discoverd like 4 plugs out of 8 is bad i will try and change plugs and see if ther will be a difference but i also tried what a friend suggested which was to remove the positive terminal and put it on the compressor for like 1 minite and put on the head lamp so as to discharge the crank shaft position sensor memory, replace the battery treminal and start the engine this actualy might have worked because i left the car idle for 1 hour with the engine running, the engine normaly goes off in less than 30 minutes befor.i will try to use the car and see if it works thanks

DougW bro pls i tried the car again yesterday to find out if the problem has been corrected but the car went off after 45 mins and it refused to start again pls acn i have ur suggestion as to what i can do next? i will appriciate ur response