Engine/Transmission (1998.5 - 2002) Is Lift Pump about to die?

[GaryKrahmer]

OK guys... . Here's the scenario... Last night myself, my daughter and my dad went and watched the Giants slaughter the Colorado Rookies 7-0 at Pac Bell park.

Had a great time. . until we had to fight all the traffic getting outta the park. We got on the freeway and I glanced at my fuel gauge and it was reading 4 pounds at 60 MPH. I thought oh. . oh. We have trouble here.

Of course this happened on the Bay bridge where there is no place to pull over. So I continued to head east.



The truck was running fine with no sign of any trouble except for the gauge reading. At 70 MPH it would drop to 2 pounds and WOT it would go to 0 PSI. I continued home and when I dropped off my dad I restarted the truck and low and behold, she's now reading back up to 15 @ idle and 12 at cruising speed, dropping to 8 PSI at WOT.



This morning I took a little trip and she looks fine, readings are all normal, but... I'm leaving tomorrow to take the family and the 11,000 pound 5th wheel camping and am a bit nervous about last night's incident.



So here's a few questions... Do you think the lift pump is about to die?



How low can the pressure get before you start doing harm to the injector pump?



How long can you safely drive the truck without damage to the pump at 0 PSI?



And. . if I have to change my own pump because the dealers service department is not open... . How much does a new pump cost?



Thanks for your time and knowledge.

 

[SEmerson]

Yes your pump is on its way out. Get one at cummins and put it under seat. Views are mixed on how low is too low but 0 anytime is very bad. I would say 4 at wot is the very lowest you should ever see. It is not hard to change on the road if needed. Thay are expensive but still about 1/2 price at cummins.

 

[TSRAM]

Sounds like the pump is headed south. Mine is apt to almost stop pumping once and awhile also. I put a pusher on mine and it seems to help the lift pump last a little longer. I have bought a new one already, but haven't installed yet. Want to get all of the goody out of the old.

The new one from the local cummins dealer was around $150 out the door. The pusher is a carter from napa at about $70and has been helping for around 6 mos. with a tired lift pump.

 

[Mad Bomber]

Lift pump

Raatler,YES it's going south you had better change it VERY SOON. When you put more stress on the engine I. E. pulling a trailer it will kill it faster. I would get very up tight with seeing 5lbs for a long time. With the lift pump so low it will not cool the injection pump well. When mine started to go it warned my about 2 days before it was dead. GET ONE FROM CUMMINS. You will need to know your engine serial # on drivers side near the ijection pump. Eric

 

[RobbyRam]

Mine did the exact same thing. Get a new one at Cummins West and take it with you. A 15 minute change if you move the fuel filter out of the way and go in from the top. Change it in the campground between vollyball matches

Bob in Sacramento

 

[plongson]

How the heck did you change it from on top?? You can hardly get your hands in from the top let alone see what you are doing...

 

[RBSOB]

WHOA!!!!

Just had the same scenario, fluctuating pressures, sometimes ZERO, then back to normal for my truck. Bought a new pump at Cummins and replaced (from above,took about 30 mins. do a search on RobbyRams technique, very easy ) All was fine for approx 1 week, 600 miles. Now, fluctuation and amount of time at ZERO is worse. I suspected all along that something other than the pump was amiss, so I kept the original as a spare. Just returned from a 1600 mile N. Carolina trip with no problems. Bosch says the VP 44 is OK with any positive pressure,and this does seem to be true but I want mine back to normal, steady readings. Anyone know how to test an electric sender unit, or just replace it? I too have a Westach 16 psi gauge with the sender remotely mounted and isolated in a rubber mount, but I have read that they do fail. Even if you buy and install the new LP keep the old one or test\replace the sender first. Don't worry too much about low readings and have a great trip. JimG

 

[Mad Bomber]

Lift pump

Originally posted by plongson

How the heck did you change it from on top?? You can hardly get your hands in from the top let alone see what you are doing...

You must remove the fuel filter and the you must almost just lay on top of the engine to be able to reach the lift pump

 

[DBoyd]

I am getting ready to change mine out and was wondering where to get the washers for the banjo bolts. I am sure to loose several during the project!!

Thanks.