Engine/Transmission (1998.5 - 2002) What is a good average fuel pressure ??

[mediccummin]

Just got done with my fuel pressure gauge and was wondering what the average is around here. I think mine is a little low, 9 at idle and 2 wide open. I will change my filter but it should not be to bad. Does it sound like my Lift Pump is going south. Any numbers would be great, thanks. I did a search and came up with some info but looking for more. Later... ... .

 

[Turbo Tim 1]

I would say yes it's time for a proper burial. Mine is 14 idle and with the comp on I can suck it down to 5 psi. About 10 psi cruising the highway at 73 mph. I am going to re-pipe everything in 8an soon that should help mine at WOT and highway speeds. I really hate to see it below 10. Just my 2 pennies

 

[Ron Bissett]

You will need a pump replacement now if not sooner. It on its way south new pump should get 14to 15 idle and never under normal cruse 10 psi . GET PUMP at Cummins $ or Dodge dealer if under warranty the box could strike that out depends on the dealer. You know that . LOL Ron Bissett in Metro Louisville KYOo.

 

[jbone]

Just put in new from Cummins pump ($160) and new electronic pressure module and meter from Westach---it is working really great, but to the point--15-16 can't really get it to drop much, but I only?? have an EZ box, so not over fueling like some of the guys! Just kidding guys!?! R, J. B.

 

[Turbo Tim 1]

Jbone - Have you confirmed that pressure with a mechanical gauge? When my first lift pump was replaced the truck was bone stock, even the stock air filter, and I could draw it down a couple psi.

 

[EricBu12]

I redid my fuel system, I put in a pusher 7# and a prefilter 30 micron. that made my PSI too much so I put in a regulator after the stock pump and routed the relief back to the prefilter so now even the pusher has a small head pressure.....



So now I see 13-14 psi idle, 12, cruise, and no less than 10 WOT because of the better flow. I can adjust these PSI #'s with a turn of a nut either up or down. I might have to get it up a pound since the weater warmed up, it has gone from 14 or so to 13 at idle.



I have 2 boxes making 331 HP at the wheels and 30 PSI boost and still the FP is no less than 10 PSI... .

I believe I have a very reliable system since none of the pumps are working hard.



I also just put in a 18 gal aux tank as you might have seen and the 7# and bleedoff from the regulator helps serve to siphon the fuel from the aux tank to the main as I use it... .



Search "my fuel sytem setup finally done" to see a diagram of my setup.

 

[EricBu12]

heres the setup



<img src=https://www.turbodieselregister.com/user_gallery/sizeimage.php?&photoid=5926&width=2/src img>

 

[JPLB22]

I have just recently installed a DiPricol mechanical FP gauge. At first I was using an isolater and my psi. would always go up 1 - 2 psi after start no matter where it started. For istance if it was sitting on 5 psi and then I started the truck it would go to 6 - 7 psi or if it started on 0 psi it would go to around 2 psi ( which had me very worried ). So yesterday I removed the isolater and have diesel all the way to the gauge and my gauge now shows:

14 psi at idle

10. 5 psi WOT

12 psi on freeway at 75 - 80 mph



Running diesel to the gauge is more accurate IMO.



Before installation of the DiPricol gauge I checked FP with a hand held gauge and was getting 12 psi at idle. At the same time as the gauge I did a fuel line kit and my psi increased by 2 psi at idle !!



My truck is an '02 and does not have any extra fueling YET.

 

[RustyJC]

With 15,000 miles on the original lift pump, pre-filter pressures are as follows when towing our 13,500 lb 5ver:



Idle - 16+ psig

Cruise (65-70 MPH) - 15-16 psig

WOT - 13. 5 psig



I had my post-filter sending unit shut off at the gauge snubber during this trip, so I don't have any post-filter data - typically, it's 1 psig lower at cruise and WOT.



Rusty

 

[mediccummin]

Thanks everyone

Thanks for the info. I will change my filter first to see what I get. My gauge is the new autometer electronic sport comp. This is a new sending unit from what I was told. The wires go straight to the gauge. I have my sending unit mounted to the fire wall with 3 ' of hose coming from my lift pump tapped banjo( wildcat ).

As far as warranty, I am still under warranty. I have the extended to 100,000 but I will not go back the the #$%*&*#^ again. Since I posted bad things about them on here I was called by the service manager never to come back and cussed up and down by him. He said he would warn the other dealer of me and that I would be blacked balled in the whole county. This has happened, I have not been able to get any warranty work done. No replies from DC on my letters or phone calls. Besides everytime I took it in for something they would brake or screw something else up and I would have to take it back again. I posted once that I was at around 27 trips for repairs for mistakes they made. Truck spent a total of 2 wks in body shop for dents they put on it.

Anyway I guess I'm saying I would rather eat it and fix it myself. Then I know it will be right.

Any suggestion and prices on pumps. What is the cost from Cummins for a new one?????



Thanks again. Dwayne



P. S. THE DEALER THAT CHEWED ME OUT WAS CROWN DODGE IN VENTURA CA. DON'T GO THERE THEY WILL SCREW YOU... .....

 

[Turbo Tim 1]

Yesterday I paid $148 plus tax at Cummins Northeast in Albany for a new lift pump

 

[krs]

My stock pump is almost as good as Rusty's with solid 16 at idle, 14 at 70 mph cruise, and down to 11. 5 -12 at WOT. Just about to turn 20,000 miles. Those are prefilter numbers. Postfilter was 1 psi less until last week. It's gone down to 2 psi after filter now. Guess the filter is getting full. I have a mechanical backup gauge under the hood that verifies the electric's readings.

 

[mediccummin]

Update

OK I went the dealer route with no luck, they wanted to pull there all week we need your truck your gauge is'nt trustworthy and we need to flow test it routine bull$hit. So I went to Cummins and bought a new one and did it myself in about 20 min. Paid $148 plus tax and they sold me some wire I did'nt need but said is was necessary. I will try and take this worthless wire back.

But anyway, I get 14-15 at idle now, 12-13 cruising and 7-8 wo. Much better than my earlier posting. Seems to have much more throttle response and runs better.

Thanks to all the replied with some help here. TDR is a great place..... Dwayne... ...

 

[CFAR]

Did they charge you extra for the pig tail?



Mine was included for the $148.



Keep your old pump as a spare, it will get you home if the new one dies.

 

[mediccummin]

YEP

$7. 00 extra duckets, thats why I'm taking it back and they better not try and charge me a restocking fee. Thanks and yes I did keep the old one for a spare, put it in the extra parts box I take on trips. Later... ... .

 

[juicedcummins]

From what I see and a few others the factory lift pump is a lot better than given credit for. The problem is the stock fuel system [lines etc] and the location of the stock lift pump. It also needs a better power supply from a relay.



I see; 16@idle

15@ 80 mph + cruising

13@ 5/5 on comp to the boards from stop till wound out!





I'm not fueled as high as some but more than the average. I don't know what this thing is putting out because it keeps slipping the dyno around the 280hp mark long before it's maxed out. [a wild guess would be 340-350hp. It will make 42lbs of boost.

Pusher pumps are just a band-aid on a poor factory design which just complicate things and ad cost. Reliability is questionable with the possibility of 2 electric pumps to fail. I know I ran them myself in the early 90's on another application, which convinced me the mighty Cummins needed a better solution.

 

[rweis]

With AN-6 tank to VP and LP by the tank I get the same as RustyJC with an 8k 5er.



I did have a Westach solid state sensor go south after 1 year. It measured post filter, was on a 18" snubber line with a needle valve snubber. Westach replaced it no problem.



I do add fuel additive every tank to help lubricate the LP and VP and to remove water.



17k and running fine on OEM LP.



Bob Weis