You have my engine. If the vehicle does not throw a code I would test for two things initially - the fuel delivery and an electrical short. A bad sensor will typically throw a trouble code.

To test the fuel delivery you can probably rent a fuel pressure gauge from the local auto parts store. With our vehicle you can connect this gauge directly to the fuel rail easily because there is a fitting. You should always have over 50 psi of fuel pressure whether driving or at idle. You can attach the fuel gauge to the rail and put the monitor on the windshield, have a friend drive, and you monitor the gauge.

Second, you can test for an electrical short with an inexpensive multi meter. Put one lead of the meter on the negative side of the battery and put the other side on a shiny part of the engine while it is running. It should read less than .5 volts. If it reads more than .5 volts you may have an intermittent ground wire short on the engine. The next test is to put one lead of the meter on the negative side of the battery and a shiny part of the vehicle frame with the headlights turned on to provide an electrical load. It should read less than .5 volts. If it reads more than .5 volts you may have an intermittent ground wire short on the chassis.

My bet is the fuel pump is going out.

 

You have my engine. If the vehicle does not throw a code I would test for two things initially - the fuel delivery and an electrical short. A bad sensor will typically throw a trouble code.

To test the fuel delivery you can probably rent a fuel pressure gauge from the local auto parts store. With our vehicle you can connect this gauge directly to the fuel rail easily because there is a fitting. You should always have over 50 psi of fuel pressure whether driving or at idle. You can attach the fuel gauge to the rail and put the monitor on the windshield, have a friend drive, and you monitor the gauge.

Second, you can test for an electrical short with an inexpensive multi meter. Put one lead of the meter on the negative side of the battery and put the other side on a shiny part of the engine while it is running. It should read less than .5 volts. If it reads more than .5 volts you may have an intermittent ground wire short on the engine. The next test is to put one lead of the meter on the negative side of the battery and a shiny part of the vehicle frame with the headlights turned on to provide an electrical load. It should read less than .5 volts. If it reads more than .5 volts you may have an intermittent ground wire short on the chassis.

My bet is the fuel pump is going out.

That's useful info. I can do both of those test relatively easily.

Do you think I could have a bad fuel pump even though the car runs perfect while on the gas?

 

Do all the dash lights act up when it stalls as if the key had been turned off then back on? That would be indicative of the ignition switch going bad.

Otherwise, does the idle act up? Ever dip down to ~500 rpm then recover? Not at all uncommon for the TPS and/or IAC (two sensors on the throttle body) to be a little fritzy and cause stalling. Can also be as simple as dirty passages in the throttle body.

 

The dash lights and everything stays on when it stalls. I have never noticed any idle issues. I although have not look at that too closely.

There was a jeep Recall for the ignition switch would switch off on people. Recall number - P41/ NHTSA 14V-438

also, I know this was a problem for some HEMI motors, but there was an issue were a faulty oil sensor/switch would shut off when it senses low oil (when levels were fine) to protect the motor, I don't know if the 4.7 motors had that or not though.

It has had the ignition recall done. As far as the oil sensor. I am not sure on that regarding the 4.7 Engine.

 

There was a jeep Recall for the ignition switch would switch off on people. Recall number - P41/ NHTSA 14V-438

also, I know this was a problem for some HEMI motors, but there was an issue were a faulty oil sensor/switch would shut off when it senses low oil (when levels were fine) to protect the motor, I don't know if the 4.7 motors had that or not though.

 

UPDATE

I took the Jeep off a 250 mile drive yesterday. Mostly highway. It had no problems for the first 50 or so miles then it shut itself off twice in a 5 min time span or so. After the second time it did this I turned tow mode on. No issues at all after that driving. I did have an issue at a traffic light where I watched the RPMs dip below 500 and then the engine shut off. Any thoughts about this and/or what tow mode would do to enable the engine to stay on besides eliminate overdrive?

 

Drive the next 500 miles in Tow Mode and see if it stalls again before drawing any conclusions. Too soon to tell if the Tow Mode made a difference.

 

I'm just going to throw this out there because I had problems with my Jeep stalling at Highway speeds and trying to leave the driveway. Not sure if you all know this already as I am new to this site and have not read much yet, but my issue was due to NON-OEM spark plugs. I decided I would throw some new plugs in it one day and decided to go with Bosh plugs. Shortly after the thing started stalling at speed, bucking, shifting screwy, you name it. It was a Death-trap at that point. After many nights researching and finally bringing it in after no luck finding answers, the Dealer tells me they don't know what's going on, but they did find that I did not have OEM plugs in it and there was a service bulletin regarding that and he would like to start there and charge me $358 to replace the plugs. Feeling pissed off that right out of the gate my bill would be $358 just to start, I said Nah, I'll come get the dam thing and change them myself. So me, thinking ok I'll get the plugs THEY want in it and bought them there, not realizing at the time I could have saved about $110 at an auto store. But I went home, threw them in and son of a gun...it fixed the problem!! Couldn't believe that non-oem plugs would have that effect. So, make sure you have OEM spark plugs.

 

The previous owner started having issues before replacing the plugs. He replaced the plugs and still had issues. I will pull one out and see what brand is used but I think as Walt said it is just for the 5.7 Engines.

Not mentioned thus far, but some members have reported that a low fluid level in the 545RFE xmission can cause stalling as you described. Presumably, a clogged filter might starve it also. If you do not have good maintenance records, I would suggest new filters (2) and ATF+4 fluid on a drain and refill (no flushes). MOPAR filters are recommended as some aftermarket filters have failed prematurely. When originally reported, I did not (and still do not) understand the link between the engine stalling and low xmission fluid level. At some point, you'll have to do this work anyway as a periodic maintenance task.

OEM plug issue was principally with the Gen 1 5.7L HEMI.. See thread by charlesrshell on this subject.

Other 4.7L owners can probably give more details.

Thats something I have not really checked at all. I will look and see the fluid levels and such there and see if the previous owner ever changed the transmission fluid.

Drive the next 500 miles in Tow Mode and see if it stalls again before drawing any conclusions. Too soon to tell if the Tow Mode made a difference.

Yea I plan on driving it more in Tow Mode just to make sure.

 

....
Vehicle Info:

Year: 2007
Model: Grand Cherokee Laredo
Engine: 4.7L V8
Mileage: 131,000 Miles

Items Already Replaced:

ECU (Twice)
Spark Plugs and Wires
Ignition
Crank Position Sensor

Any advice/input would be greatly appreciated.

Not mentioned thus far, but some members have reported that a low fluid level in the 545RFE xmission can cause stalling as you described. Presumably, a clogged filter might starve it also. If you do not have good maintenance records, I would suggest new filters (2) and ATF+4 fluid on a drain and refill (no flushes). MOPAR filters are recommended as some aftermarket filters have failed prematurely. When originally reported, I did not (and still do not) understand the link between the engine stalling and low xmission fluid level. At some point, you'll have to do this work anyway as a periodic maintenance task.

OEM plug issue was principally with the Gen 1 5.7L HEMI.. See thread by charlesrshell on this subject.

Other 4.7L owners can probably give more details.

 

Not mentioned thus far, but some members have reported that a low fluid level in the 545RFE xmission can cause stalling as you described. Presumably, a clogged filter might starve it also. If you do not have good maintenance records, I would suggest new filters (2) and ATF+4 fluid on a drain and refill (no flushes). MOPAR filters are recommended as some aftermarket filters have failed prematurely. When originally reported, I did not (and still do not) understand the link between the engine stalling and low xmission fluid level. At some point, you'll have to do this work anyway as a periodic maintenance task....

Have you had an opportunity to look at your xmission ATF+4 fluid level and / or change fluid filters?

 

Last night I was able to plug up a pressure gauge to the fuel rails and drive around for a bit. The pressure stayed consistent at 60-62 PSI the whole time. Only blipped slightly at 100% throttle during a gear change. Fuel Pump seems to be fine.

 

It seemed that a lot of people have said that the Crank Position Sensor was the issue but I replaced that and it still shut off.

Vehicle Info:

Year: 2007
Model: Grand Cherokee Laredo
Engine: 4.7L V8
Mileage: 131,000 Miles

Items Already Replaced:

ECU (Twice)
Spark Plugs and Wires
Ignition
Crank Position Sensor

Any advice/input would be greatly appreciated.

A couple of additional thoughts. First, make sure the crank sensor you installed was a Mopar OEM sensor not an aftermarket sensor. Jeeps are really sensitive to have the right crank sensor installed. Also check to make sure the cam sensor is OEM also. Did you keep the old crank sensor and, if so, can you confirm it was Mopar OEM?

Second, where did you get the ECU's? One Company I know of that "refurbishes" them produces junk. What was the firm the last ECU was purchased from?

Last, did you check for a short or issue with current flow on the engine and body ground connectors yet?

 

The one that I put in was a Mopar 56028666AB. It was a Original OEM part. I can check the CAM Sensor and see if it is OEM. I do have the old Crank sensor as well. I can grab a picture of it and post it.

As far as the ECU's go. I did not purchase them. My buddy did when he owned the jeep. I think his wife told me that they paid $750 per ECU. I can look and get you the serial number or whatever if that gets us anywhere as to if the ECU was a quality one or not.

I cleaned up 3 grounds in the engine bay to make sure they were making a solid connection. I did not measure to see if the voltage was >0.5v.

 

**UPDATE**


I switched keys to see if that would fix the problem. So far the car has not shut off. Last night I put the original Crank Position Sensor in the car. I am going to test out this and see if it is fixed.

 

I spoke too soon. The car shut off the engine four times within the past two days.

 

I checked it after it was warmed up. These are the results. It seemed to be half way between the hot marking and cold marking. I attached some pictures.

 

Mine has used virtually no ATF since I've owned it.

I would add 3 oz. of ATF+4 and verify that it comes to the lower HOT mark once the transmission has reached operating temperature. Go slow so you do not overfill. See directions above. You can check for a change in the stalling situation.

If it has 131,000 miles and no record of xmission service, you are overdue. Max (without severe service) is 102,000 miles. Try to see if this is needed. There are also 2 filters inside; use MOPAR OEM for both.

 

I will give that a go. It seems too clean to be the original.

 

Save your time and money. Take a look at the video linked below. Can almost guarantee that the problem is not your transmission fluid and filters. The problem could be a non OEM cam and/or crank sensor, a clogged exhaust, bad wiring...

 

I will give that a look. I did also open a case up with the NHTSA about this issue since there seems to be such a large number of Jeeps effected with this problem. Case Number: 11082351 if anyone wants to take a look at it. I also did contact Chrysler themselves about it to see what they say. So far they are not being that helpful.

 

Maybe consider taking your Jeep to a great diagnostician - not a dealer , and not someone that will "guess the problem" and throw engine computers at it.

Your engine runs well and something is turning it off. This is not rocket science. It could be a bad CAN module, could be bad relay, could be an intermittent short in the wiring due to heat and vibration. Just need someone that knows what they are doing because we know for sure it is not the engine computer!

 

Yea. I'm not sure who exactly I would trust other than myself to fix this problem. My buddy had it and replaced the ECU several times and a few other things. No engine codes come up so there is not really any direction from that point of view. If I take it to the dealer it seems from what the info that I have found on the internet more often than not they tell the customer that they can't duplicate the problem and give the vehicle back to the user in the same condition.

Im pretty confident that its an electrical issue of some sort. I would need to get a hold of a wiring diagram for this car.

 

Here are a couple part numbers of things in the Jeep currently:

Crank Position Sensor: 56028666AA (Im about 90% sure thats the correct p/n)
ECU: R5094354AF

 

I got these part numbers below from a Jeep Dealer website. The dealer often has multiple part numbers for the same part. To be sure you have the right one, I would call the dealer parts counter and give him your part numbers to look up and confirm.

The crank sensor for a 2007 V8 Jeep Grand Cherokee is part number 56044180AC for $36.90; the Camshaft sensor is part number 56041584AF for $32.90. The Powertrain control module is part number #5094611AF for $476.64.

So you do not drive yourself crazy, I would do the visual inspection as best you can, maybe exchange the relay and clean up some wire connections, do the voltage drop test, then drive the car. See if you can duplicate the problem. Find out what happens just before the engine stalls - did you hit a bump, was the car shifting, was the car turning, etc.

 

To just top up the trans, that stuff would be just fine. I prefer to use the 'correct' stuff, but in this case it's just a little bit and I wouldn't think twice about it.

 

*Update*

I put the remainder of that Valvoline ATF in the Jeep but I dont think it was enough. I might need to get a bit more to make it reach the "hot" mark with the engine at correct operating temps.

The issue happened to me again yesterday when I was at a stop. I was probably at a incline of maybe 7-10 degree. As soon as I pressed the throttle to accelerate from a stop there it shut off. Restarted the car and everything was like normal.

 

I know from my own recent experience how frustrating it is to not know why your car is stalling out of the blue. It's also very traumatic when it happens in traffic at 60 mph as happened to me. it is very tempting to throw new parts at the problem hoping one might solve the problem. I suggest you go back to the basics before buying any more parts. In no particular order I have some suggestions:
1. Have you checked the engine for vacuum leaks? You can do this with smoke from a smoke generator or a stinky cigar. You can also use brake cleaner and spray around all the vacuum hose connections and listen for a change in the sound of the idle. Be careful not to start a fire.
2. Buy or borrow a good scan tool that has Live Data. Blue Driver is reasonably priced and gives a lot of data. Autel also makes very good scanners like the MD802. You want to look at things like short and long term fuel trims. If your short term fuel trim is highly positive it would suggest a vacuum leak. You can see if your oxygen sensors, throttle position sensor, and MAP sensor are functioning normally. You can check for misfires.
3. If you buy an inexpensive DVM (digital voltmeter), and some T-Pins, you can test the circuits for all the sensors. The Jeep Grand Cherokee WK shop manual is available online in PDF format for free. The procedures are spelled out in detail. It took me a while to figure out what to do but once you learn to back probe one sensor, the rest are all the same pretty much. You have a ground, a signal, and a 5 volt reference. The wires are all color coded and the shop manual wiring diagrams tell you what's what.
4. If you have an oscilloscope you can check relative compression and check the signal traces for all the sensors. You can also check all your coils.
I learned the hard way that throwing parts at a problem can an expensive and exasperating endeavor especially when there are no codes. I recently had a similar problem due to non-oem coils. I had the correct data (secondary coil resistance) but failed to interpret it correctly until someone helped me out. Before that I replaced the oil pressure sensor, camshaft position sensor, crank sensor, and map sensor for nothing. I've spent the last 2 months learning all the above. There are You Tube videos that cover all of what I listed above.
Good luck.

 

So your issue was your coil pack?

I do not think I have a vacuum leak, the car idles fine but I will look at that.

As far as I understand whatever is causing it is something that is not monitored by the ECU since no codes are triggered.

Those data loggers, do they let you look at parameters in real time? As in if the engine shuts off I can look back at a log in that time window.

My next/current step that I am going to try is to make sure the transmission fluid is to the level that is required to reach the "hot" mark on the dipstick. I ran out of ATF fluid the other night but I will go pick up some. Found this

https://www.walmart.com/ip/Super-Tech-ATF-Plus-4-Automatic-Transmission-Fluid-1-qt/17133940

That seems like the easiest option at this moment to make sure.

 

amoffitt,

Does your Jeep have an aftermarket remote start -or- aftermarket security alarm system??? If it does, try disabling it (them) to see if some electronic interaction is causing the stalling.

All of the other things in this thread (except xmission fluid level) are areas where a DTC would likely be generated for an off-normal condition.

 

About transmission fluid level, i understand an excess is problematic, maybe?
What's minimum mark in the dipstick that i have to obtain?
I don't understand what's the influence in "engine's shutdown", thanks for your patient with me.

 

Yes. Minimum should be bottom HOT mark per the pictures in my earlier thread. Follow the procedure.

I never understood the relationship either. Seems to be only the RFE545 xmission and not a particular engine. Several threads in the past years that provide the correlation, but not the particular reason.

Several factors seem to be common:

1. maintrain xmission at the correct level
2. Ensure the fluid and filters are changed in the appropriate interval.
3. Use MOPAR filters and any ATF+4 fluid.

Things like a solenoid pack going bad will generate a DTC and limp mode. Mine did. The xmission fluid situation did not in any of the posts by JF members.

 

Hmmm....

Did all of the stalls happen when you were stopped?

Reason I ask is that I too noticed at idle at a stop that my rpms sometimes drop from the target of 600 to 400. If I put the vehicle in neutral the engine goes back up to 600 rpms AND if I then put the vehicle in drive the engine stays at 600 rpm. So something in my transmission is dragging down the idle. May be unrelated to what you are experiencing. Yes, my levels are perfect and all of my trans fluid was changed with Mopar OEM fluid less than 2,000 miles ago. I am thinking my solenoid pack maybe, do not know.

 

Update.

I have not been able to mess around with this much lately. It did go another long period of time without shutting off. I had a buddy suggest it was one of the fuse boxes since he has a similar issue with another Chrysler vehicle. Im not sure how credible that is though. I will keep you guys posted.

 

Any news? Very interested in found the solution, i'm desperated (now here it's hot and i have to start A/C, without A/C i don't have this problem).

 

***Update 6/25/2018***

I cleaned up a few things in the intake area.

MAF Sensor
Throttle Bottle
IAC
Throttle Position Sensor

The issue came back again. My next step is going to swap transmission fluid and filter. With that said, does anyone have the correct part number for the OEM Transmission filter that I need?

 

***UPDATE 7/2/2018***

After looking at a few things and what I know about vehicles I was not able to sell myself on needing a transmission fluid and filter replacement. I did however scan the computer again this time with a Snap-On reader and found code B2185. At this time I am trying to determine what relation this has with the problems that I am having.