Engine/Transmission (1998.5 - 2002) Time for a lift pump?

[LBTRS]

Got my fuel pressure gauge from briar hopper today and tested out the truck. I get 15psi at idle, 10 psi cruising and 5psi at WOT. Will the dealer do anything with the 5psi at WOT?



Thanks for any advice.

 

[beartrace]

I took mine into the stealer with about the same numbers that you have stated and they replaced the lift pump with no questions asked. I also called DC hot line before I took it in and they said it was all covered under warranty. Told me to just give them a call with the dealers name if they did not want to cover it.

 

[Snow man]

Ray,your pump is fine. Your pressures are all good,the only reason your WOT is under spec is due to the ez and 275's. Also i always change the fuel filter out and retest FP before you change the lift pump.

 

[EMDDIESEL]

My numbers were worse and they gave me a hard time and said they wanted me to leave the truck so they could do a road test, no way am i letting those clowns drive my truck. I did it myself. Cost alot, but i know its done right.

 

[WyoJim]

Words of wisdom from the Snow man... . Finally some one with some lift pump logic instead of complete paranoia.

 

[LBTRS]

Snow man,



Thanks for the info... Changed the filter just last week so I'm sure it's good. Will check the fuel pressure regularly for any changes.



Thanks again

 

[zimman20]

Snow man- That is not my understanding at all. The way I understand it the LP should maintain pressure regardless of how much is being called for, EZ or mods or not. DC's new spec (we are told) is 8 PSI minimum at all times. His idle and cruise look ok but his WOT number is not good according to DC spec.



I wouldn't call this LP paranoia, in fact I would say this is an LP that is on its way out. Technically he should be able to get it replaced now per DC Star line spec. If there's any question about this, try unplugging the EZ and take it for a ride, see if the numbers change.



Never heard of such a thing as a modification(s) being expected to lower LP pressure!!



Thoughts?





zman

 

[Steve Campbell]

I did not see it in your sig....

Have you done anything to the fuel lines? Even the "Ray's" (how about that) banjo bolts help get more fuel to the VP. You could also drill out your own... . but be careful of cleanliness!!!

 

[Big White Beast]

Similar numbers.......

14 idle and 11 or so cruising then down to 4 at WOT.



After new pump:



Couldn't suck the pressure below 11 psi even with DD2's and the EZ.



I added a pusher to ensure this pump lasts longer and maintains pressure even under WOT. Waiting on a Dakota digital gauge to read higher pressures from adding the pusher. Had a 0-16 Stewart Warner and it maxed out post filter. The DD gauge is 0-30 so I'll get more accurate readings.



Garrett

 

[zimman20]

Thanks, BWB. Didn't think so.

 

[beartrace]

I have 275's and EZ and before the lift pump change I got a 4 reading at WAT. After DC changed the pump under warranty, it will not go below 12 at WAT. I would go and see the Stealer for a new upgraded pump.

 

[WyoJim]

"Much to do about nothing"... "Making mountains out of mole hills"..... "Paranoia"... . "Panic"

 

[zimman20]

WyoJim- In fact, my LP was reading <0 PSI at WOT when it was changed. seeing 8+ PSI WITH EZ after change.



You could make the argument that anyone with 5 PSI is concerned about nothing and that would technically be true 'at this time'. However, bet ya a paycheck that the end is near for

the life of that LP and it bears watching.



My point was that the EZ or other mods would not be 'expected' to lower the PSI being put out by the LP, that should remain a constant regardless of mods. That was a bogus statement.

 

[Snow man]

I still dont think its dead,my dad's 01 with a brand new pump 16 psi guage pegged at idle will suck the pressure down to 5psi after being WOT for about 8 seconds with dd2's,and an EZ,this is with stock banjo's,and a brand new fleetguard fuel filter. His oringinal pump had 10psi at idle,4 criusing,and 0-1psi at WOT throttle,it was almost dead. Ray's pump is not even close to this,id keep running it if it were mine.

 

[Big White Beast]

Last legs........

Some of these lift pumps will give whacky readings. Someone from up north was vacationing down here and was worried about his pump. My original mechaincal gauge makes for a nice temp set up so I had him come over to test it.



0 psi when we first hooked it up. Took it for a test drive and after the VP sucked some fuel it suddenly jumped up to normal readings. Came to a stop light and it had pressure at idle for a few seconds and fell to 0 again. Seemed it couldn't suck all the way from the tank without help. Once it was up and going it seemed to work somewhat normal.



Anyway the dealer replace it when he got home. It was a saturday and the dealer didn't have one down here and Cummins was closed.



I'm impressed with the pressures added by the pusher pump in mine. I would recommend it for anyone. It cost less than the lift pump. If yours is on the edge add a low pressure pusher and help keep it alive. If the lift pump has a steady supply it can keep up the required pressures easier.



Garrett