Ongoing Fuel Issue Leads to Stalling

[Ellis32198]

Hi all. Haven't posted here in a minute and I must apologize up front, it's long and a doozy.
I'm hoping I can get some direction toward a resolution for this issue as several mechanics, along with myself, have not been able to troubleshoot and correct the problem. So here goes and thanks in advance.

2010 Dodge Ram 3500 DRW Laramie - Stock
214,000 miles w/ all regular, prescribed maintenance items current
VIN 3D73M4CL3AG136415

Beginning in March 2021, I started having the common 1/4 tank stalling issue notorious when the lift pump pickup screen gets clogged and starves the engine of fuel. So to remedy that issue, I dropped the tank, pulled the pump, cleaned it up, and reinstalled. Found that evolution did not correct the problem after driving it, now the 1/4 tank stalling issue has turned into a 1/2 tank stalling issue. So I replaced the fuel pump using the same procedure. Again, that corrective action did not work. Drove it like that for several months towing a 5th wheel around the country and back, just didn't let it fall under 1/2 tank.

Three weeks ago I made an appointment with a local mechanic for them to troubleshoot and correct the issue. After explaining the symptoms, my remedies, and left it with them for troubleshooting, they stated they were going to empty the tank, clean it out, and test every vent. They ended up only pulling the pump, bench-testing it, and determined it was a faulty fuel pump. Even after explaining that the 1/2 tank issue began before installing the new pump, they were adamant that the faulty pump was the issue and replacing it would correct the problem. Unfortunately, the part they tried ordering from the dealer was discontinued and I was forced to source the part myself. After several iterations of incorrect parts and 3 weeks later, they completed the work and returned the truck to me, without testing to see if their corrective action actually worked. It did not.

So, they were wrong. I picked up the truck yesterday and drove it this morning. Low and behold, right at the 1/2 tank mark, the engine sounds like it's starving for fuel and threatens to stall in the same fashion as before. I am livid! I called the shop immediately and they refuse to look at it again for another 2-3 weeks or provide a refund.

The only other causes that I even remotely considered an option would be either the CP4 or one/both of the 2 small plastic (vinyl/neoprene?) fuel lines that attach from the hard steel fuel lines to the top of the pump on the tank that may have gotten crimped during my first tank drop. I am seriously at a loss. This issue has been looked at by a diesel mechanic at Dodge dealer and a private mechanic, neither could diagnose and correct the issue.

Any ideas or direction would be greatly appreciated!

 

[Spud66]

Hopefully this is resolved but...

Maybe the lower fuel level is exposing an air suck condition.
1., Test the fuel flow at the front fuel filter by putting into on and let it drain into a bucket or fuel can. Take note if it looks foamy.
2. Let it get down to failure condition and do the same.

=is the same amount of fuel in the bucket for the same run time?
=is it foamy indicating air suck if pump is in tank one would think the slight level change would not affect it.

Final thought this is what a fuel pressure gauge is for. it is critical on vp44 and needed to troubleshoot this kind of failure. Does it do it when fuel is relatively cool or only when driving for a long distance towing which could be fuel temperature change.
EDIT: looks like 8th digit is L meaning diesel if gas ignore most of my post.
Let us know take care... JR

 

[Ellis32198]

Hopefully this is resolved but...

Maybe the lower fuel level is exposing an air suck condition.
1., Test the fuel flow at the front fuel filter by putting into on and let it drain into a bucket or fuel can. Take note if it looks foamy.
2. Let it get down to failure condition and do the same.

=is the same amount of fuel in the bucket for the same run time?
=is it foamy indicating air suck if pump is in tank one would think the slight level change would not affect it.

Final thought this is what a fuel pressure gauge is for. it is critical on vp44 and needed to troubleshoot this kind of failure. Does it do it when fuel is relatively cool or only when driving for a long distance towing which could be fuel temperature change.
EDIT: looks like 8th digit is L meaning diesel if gas ignore most of my post.
Let us know take care... JR

Thanks for your input @Spud66. I wish this was resolved!

Yes, this is a diesel, sorry for not including that info!
The air suck condition has actually been a leading theory of mine that I've expressed to each of the mechanics, but they've decided to forage for other causes.

I haven't considered a temperature connection to this yet as the issue has only occurred while driving for long distances in varied heat and cold, but very well be a factor. I'll take note of this.

As for your troubleshooting recommendation, I can make the attempt, but my recent event with this issue may provide similar results.

Last week I was towing the 5th Wheel in the D.C. area where, for some reason, they have very limited fueling opportunities for large trucks and semi's. So, and not having a safe place to stop to add the 10 gallons fuel cans we have with us, we attempted to stretch as far as we could in order to "limp" to the next fuel stop on the interstate. The gauge passed below 1/2 tank without the usual power loss, so we pressed on, reaching the exit ramp to the fuel stop it finally showed signs of stalling. I was able to drive it all the way to the pump!

After filling the tank, the engine wouldn't start. Probably shouldn't have turned it off because apparently the system lost prime. It wasn't until several unsuccessful attempts at refilling the filter housing with the tank's lift pump, that I went ahead and filled it manually. There was only about 1/4 of the normal level of fuel in the housing.

It still took several more attempts to get it started, but it finally did. And it operated well, like nothing ever happened.

Don't know if this helps identify the issue, but it certainly helped me unload my frustration. Thanks again for your insight.

 

[Spud66]

Hi Ben

These are self priming dont fill the filter housing. To prime turn key on and you should hear the pump. You may have to bump it but I dont think so. Let it wiz right on the parking lot. Cycle the key til it stops humming about 3 times and it should be primed. It sounds fuel delivery with this info. You need a fuel gauge to monitor this. I would like to see you revisit the pickup in the tank. There is a guy on CumminsForum called TCDiesel. He helped me with a pickup diewsel swap in a cabchassis. It almost sounds like if it level dependent consistently that there is really something wrong with the in tank pump or pickup. I may call him tonite to run this by him. Another thought is the fuel system may be vacuum locked but I am not sure how it vents ... probably the cap. when it sputters maybe crack the cap?? I am grasping. ttyl. JR

 

[Spud66]

TCDiesel says it is a vacuum lock issue. He says crack the cap and it is your issue.

 

[Mister Luck]

Not that you don’t seem not to be a like able person
but if someone placed a ping pong ball in your gas tank perhaps it wouldn’t contact the intake until it was 1/2 full and the lack of fuel overheat and kill the pump ?

In some non diesel rams the problem is the fuel filter gauge combination and replacing both as a whole and not as separate parts solves the issue of a faulty gauge that becomes corroded from condensation of leaving the fuel tank only half full for extended periods . But I believe that part has since been replaced/ updated with one that does not corrode if exposed to the affects of moisture.

Your diesel’s system I assume has a separate filter for moisture and this is not related to some issue with that filter ?