Engine/Transmission (1998.5 - 2002) intermitant lift pump failure???

[merryman]

I set out on a trip today, and about 20 miles out, the engine started to stumble, when I looked at the pressure guage, it was at ZERO!

The truck would run, but very poorly. I limped into the next town, about 2 miles, and parked and turned it off. Since it was only 5:30 AM nothing was open. After a few minutes, I started it and all was well, with 15+psi, so I went on, the pressure was normal---near 15 when just cruising at about 55 or 60, and dropping to about 10 under excelleration. I have a pusher pump with a spin on filter before it. . About 15 miles later, the guage again went to zero, and with in a few seconds, the engine started stumbling badly and I could barely maintain speed; it go worse, untill it would hardly keep going. I pulled off and turned it off. After a few minutes, I cranked it and it took several seconds to fire, and ran poorly. I limped on about 2-3 miles to the next town. After setting about 2 hours, till a garage opened, it started and ran normally.

The two mechanics, thought it was a blockage type problem, so we replaced both the OEM and the aux. fuel filters.

All seemed well, so I went on. Fuel pressure was normal, and the truck ran great, for 45 miles, when suddenly pressure went to zero, and the engine started to miss and stumble. I by-passed the aux. pump, to see whether that made a diff. It did not. Again I limped (barely running) into the next corner store with a phone and called for a tow.

I was towed by a 1972 Ford that the operator bought NEW. Anyway, when we got to his garage, the truck started and ran fine and pressure was normal.

We replaced the lift pump, and I drove 45 miles home, with pressure--14 idle, 10 to 12 normal cruising, and about 6. 5 at WOT.



Is it solved??? I am not sure.



Is this sort of intermitant failure common???

I would appreciate any views.



Vaughn

 

[DieselHam]

Mine did the same thing, kind of!



Less than 28,000mi and my Dakota Digital gauge was flashing at me, (set to flash at below 6psi), it was reading 1. 6psi.



I shut it off and re-started, it came right back up to 12. 4.



Kept doing this for about a week until I convinced the ******* to replace it! That is a whole different story!



New pump runs 11. 6 at idle. Weak, but the ******* won't replace it as it's "in spec".



I will never take my truck to Bellevue Dodge for service again!



Good luck. .



Leroy

 

[jrobinson2]

My sister in law asked me how long it would take to change the fuel filter on her dads '99 24v, I said about 10 minutes, 45 minutes later I finally got it started. On his truck the lift pump ran when I bumped the key but when I started the truck it died after running about 5 seconds, after that no more lift pump noise, I tried bumping the starter several times with no luck so drawing on my years of mechanical experience I beat on the lift pump with a large screwdriver handle, turned on the key and got the short buzz, bumped the starter to fill the filter, then had to break 2 injector lines to start the truck. The dealer wouldn't change his lift pump, they said the diesels dont have an electric pump and he should have a professional change his filter next time

Jared

 

[Little Bill]

That's the way mine failed, too. It started out kind of random. The first 2 times it happened the truck died. Then I started paying more attention. I've got digital gauges and I could see fuel pressure go negative. When I saw pressure start falling I'd pull over, shut it down and bump the lift pump until pressure returned to about 15 and then crank up and go. By the end of the week I could make it happen anytime I accelerated 'briskly'. A new pump cured it 25000 miles ago.

 

[bdaniel]

I had the very same problem.



Pressure would be fine for seconds or a few minutes after start up and then drop to 0 at cruise or about 3-4 lbs at idle.



I could shut it off and restart and the pressure would be normal again.



When bumping the starter, the lift pump sounded ok, but the pressure would drop from 15 lbs to 3-4 after about 5 seconds of the 30 second run.



The dealer tested the lift pump and it failed some of the volume tests. They replaced it and all seems well.





Bobby

 

[KWIKKURT]

Merryman, Call me I have a suggestion or two. Kurt 505-534-0434 monday after 9

 

[muchsnow]

[

Is it solved??? I am not sure.



Is this sort of intermitant failure common???

I would appreciate any views.



Vaughn [/B][/QUOTE]



The oem lift pump is a positive displacement pump, under the right conditions (seizure) it could block/restrict fuel flow.

Or the vanes could stick in the rotor. pump will run, allow fuel to pass through, but now is just decoration.



They need to build this thing like a oil pump, simplicity/longevity.

 

[Mad Bomber]

Lift pump

Sounds like what mine did when it was dieing a slow death.

 

[LSMITH]

My original lift pump died at 116K miles and did it almost exactly like yours did with the exception of running bad, my truck ran great even with 15 PSI of vaccum on the gauge It would just start and stop at random, still making about 12 PSI at idle when it was working.



New pump (no pusher) makes 16 at idle and stays running. It does drop to about 3. 2 PSI when WOT but I am not worried at all as long as it has pressure.

 

[Mad Bomber]

PSI

I lost my 1st LP at 36. 6K and that was even with a pusher pump