Lift- Pump

[JEMOORE]

Just checked my fuel pressures.



Old Fuel Filter

Outer Port (pre fuel filter) Idle 12. 5 WOT to redline 7. 5

Inner Port ( post fuel filter) Idle 10. 0 WOT to redline steady decline to 0.



New Fuel Filter

Outer Port, as expected, Idle 12. 5 WOT to redline 7. 5

Inner Port Idle 12. 5 WOT to redline 7. 5-7. 0



I hate to admit it but this is the first time I have changed my fuel filter (20,085 miles). However it looked OK, a little black but no crud. Those pressures tell a different story, it sure needed to be changed.



These trucks should all have fuel pressure gauges. I'm not worried about my zero reading because it only happened at Wide Open Throttle (WOT) and replacing the dirty filter put the pressure back where it is supposed to be. (I suppose, I don't have a manuel but I think I read as long as there was a positive pressure it was OK?)



We really need to find out what is failing in the pump. Electrical or Mechanical, wear or foreign matter, electric motor burned up,etc. What is the pump veins or impellors made of plastic or metal? Is there at least a strainer or screen on the fuel intake in the tank? Seems there should be some kind of filtering device before the fuel enters the lift pump.



Thanks for your reply, csutton7, I agree, if we all put our heads together we will figure this one out. Maybe we already have, but I really hate to cut my lines and add more relays and pumps at this time. (although I probably will if we can't figure out any other way!) You may be right Chris, but in my mind I just can't see what would be different in a pump pushing or sucking the fuel. The distance I can understand. I just seen this in your sig. Mallory110FI lift pump gravity fed w/ BG5000 prefilter. That sounds like something along my line of thinking. If you have time may you could explain that in a little more detail to me.

 

[EMDDIESEL]

I agree, a fuel pressure gauge should be mandatory. As for the screen or strainer Pre fuel pump, i would not go with that idea since anything that does not have a large surface area will clog quickly and you be back to having low fuel pressure and will be forever cleaning strainers.

 

[swamp rat]

Having just completed a tank dropping/cleaning ceremony last week, I know for a fact the '95 models have at least two fuel screens in place before the lift pump, and I have little reason to believe much has changed in the 24V trucks. The screen around the bottom of the tank sending unit is made from same material that the pre-screen filter below the heater unit on the 12V trucks. It is little more than a plstic frame with fine mesh attached to the frame. One is large about 3. 5-4 inches in diameter, the other is barely 2 inches in diameter. On the 24V this small filter may have been eliminated, but I'm really not sure.

 

[JSoloman]

Hey guys,



You know I've read so much on lift pumps or should I say faulty lift pumps. Its had me worried. I'm not all that skookum on crawling under the hood to work on my ride. I rely on those yahoos at the shop. But this lift pump problem really had me bugged. So, I broke down and called the service dept at the Dodge dealership where I bought the truck.



I told them of the many guys out there that have had their pumps go bad on the 2000 and 2001's. Is there a recall or what? The answer... . Yes, there is. It depends on the year and whether its a 2500 or 3500. I guess that narrows down what plant manufactured the truck and where all the faulty pumps were shipped.



By giving the tech my VIN number, he was able to look up my truck and engine. Fortunately mine isn't one on the recall list. He suggested anyone else I know, to call up and have their VIN # checked out, if they have a concern. Otherwise, those with the bad pumps should be receiving a letter to get it replaced.



Get the word out. I'm sure I ain't the only one worrying about this.

Jen

 

[Steve St.Laurent]

JSoloman, a LOT have died on 1998 and 1999 trucks as well. Here's a list from a poll I did on the GLTDR and SETDR sites listing lift pump failures on trucks and how many:



2 in 25,000 miles (2001)

1 in 32,000 (1999)

1 in 17,000 (2001)

1 in 34,000 (2000)

4 in 80,000 (1998. 5)

2 in 54,000 (2001)

1 in 47,000 (1999)

1 in 39,500 (2000)

1 in 33,000 (2000)

1 in 16,000 (1999)

1 in 36,000 (2001)

1 in 36,000 (1999)

 

[EMDDIESEL]

My dealer mentioned the recall to me also, but said my truck was not covered. They said they would change it anyhow, i told them forget it, but that another story.

 

[Ken B]

Is there anyway to tell if a lift pump is going bad (or has failed) without a fuel pressure gauge? Will you notice any decrease in performance? Any potential damage to the engine? -Ken

 

[EMDDIESEL]

I did not notice any difference at all or lack of power, yet i had ZERO psi at WOT. I dont know how long my stock pump was dying for, it could have been months. But my truck seemed to be fine.

 

[JSoloman]

So, could someone explain how a lift pump can be dead or near and the truck still run? I get the impression the pressure gauge is the only way to tell or you'll go merrily along without a clue. What am I missing here?

 

[Bigsaint]

JSoloman, when they die, they die a slow death. You might not notice at first without a FP gauge. My Carter started to loose it's will to live at a bit over 2000 miles. At the time, my only HP enhancement was the Edge EZ and I didn't have a FP gauge then. I had a real bad stumble, lost all power while the Cummins was spitting and sputtering, spewing white smoke. When the truck went into A. W. D. for some upgrades. I asked Mike, the owner, to check my FP. The results were 4 psi's at idle and zero at WOT. This was a couple of hundred miles after the stumble. We replaced the Carter pump with a Mallory 4150 and all was good for about 4 months. I also put in a SPA FP gauge after I got the truck back from Auto Wurks. For about one week before the first Mallory pump died, I would see very random readings of FP that went from 2 to 16 to 10 psi's, etc, but with no stumble. I passed this off as the electrical sender going bad in my SPA. Then, one day, I parked my truck at idle. My psi's were at the normal 12 when I left. When I returned my psi's were reading -11, that's minus 11. I thought that the sender had finally taken the dirt nap until I started to move, and it was very obvious from the trucks lack of power that, indeed, my Mallory was dead. Bottom line is that you may not be experiencing any operating difficulties while your lift pump is going south, initially. I also have come to the conclusion that not all VP44's are built alike, some will stand this minor set back while some will throw their hands in the air and give up with the slightest lack of lubrication from the flow of fuel, IMHO. Hope this helps !!!



Scott W.

 

[Maximus]

Bad Lift Pump

I had a lift pump go out at 33000 miles on my 1999. It took 3 dealers to figure out the problem!



The truck lost its prime and would not start. They had the truck for 1. 5 weeks in So. California.



About 1 month later it got real bad on a trim from So. California to Seattle WA. It had a major stumble, It didn't want to go over 60mhp on flat land. Hit a hill... . down to about 40 WOT. That dosen't work well on an 1100 mile trip one way!



I had to get fixed!



One dealership in the Seattle area had no idea what the problem was. I call Chrysler and they had it towed to another dealership... they figured out the problem.

 

[JSoloman]

Thanks Scott for the details! Thanks guys for the help. This is a little frustrating for me. Looks like a pressure gauge is a must and then watch what happens. I don't know about you all, but my experience with mechanics isn't pleasant. I like to be able to drive in and tell them exactly what to look for. What I'm learning here from everyone gives me the edge to be able to do that when a problem arises.



I may not be able to work on the darn thing, but I will bet ya I'll be standing over top of em when it gets worked on. I know enough about what I'm looking at to not be made out an idiot.



Jen

 

[Bigsaint]

Jen, your welcome, glad I could help. My advice to you is to jump right in and start doing the work on your truck yourself, at least the gauges, oil/ fuel filter changes, etc. None of the work is hard and there are more than a few of us here on the TDR that willing to help with any questions that you may have. The more work that you do on the truck, the better you will get to know same.



Scott W.