Engine/Transmission (1998.5 - 2002) fuel pressure

[blubyu]

how much fuel pressure is safe on the vp pump. i currently have 19 psi. is this too much?

 

[Doug1810]

have been running 18 - 20 psi for 30,000 miles no problems min is 13. 5 psi from what i have gathered

 

[HSpiering]

need to go to carsondodge.com and ask john holmes. he has a post on that and looks like year of truck makes a difference.

 

[DMcPherson]

that is fine. there are some threads that say that there is a maximum pressure, there is not. the pressure will change the calibration of the pump but will not hurt it.

 

[Cummins724]

how much fuel pressure is safe on the vp pump. i currently have 19 psi. is this too much?

I've been running 25psi with no problems winter or summer.

 

[blubyu]

thanks for the info. i turned it down to 15psi just in case. still am holding a good 10psi to 12psi at wot that's with the comp on 4x4. the vulcan big line kit is the way to go. although i did not use some of the direct 90 degree fittings instead used some nice sweeping fittings from "summit"

 

[LKjernasen]

Low fuel pressure

Hi guys, I'm new here, living in Norway, have a -99 RAM2500 4x4 TCD an I have an issue with my fuel press who goes the other way. The case is, when I have little fuel in the tank (under half and down) I have a normal fuel press, around 15 psi idling and 10 - 12 on wot. But when I fill it up, I loose my pressure?? Then it's 10 idling and down to zero wot? I have a FASS 95 pump installed last autumn and it have been working fine until now (last two times I fill up the tank) I checked the fuel filter and it's ok, drained the water separator and cycled the pump and then, when the pump was cycling, the press was steady at 18 psi. Aha... case closed i thought, and started up, but no more than 12 psi on the manometer and falling... someone out there who have an idea?? I need some help up here at the arctic circle... I don't want to have a breakdown in the middle of nowhere in minus 32 degrees.

 

[WBarker]

Hi guys, I'm new here, living in Norway, have a -99 RAM2500 4x4 TCD an I have an issue with my fuel press who goes the other way. The case is, when I have little fuel in the tank (under half and down) I have a normal fuel press, around 15 psi idling and 10 - 12 on wot. But when I fill it up, I loose my pressure?? Then it's 10 idling and down to zero wot? I have a FASS 95 pump installed last autumn and it have been working fine until now (last two times I fill up the tank) I checked the fuel filter and it's ok, drained the water separator and cycled the pump and then, when the pump was cycling, the press was steady at 18 psi. Aha... case closed i thought, and started up, but no more than 12 psi on the manometer and falling... someone out there who have an idea?? I need some help up here at the arctic circle... I don't want to have a breakdown in the middle of nowhere in minus 32 degrees.

It sounds like your lift pump on the block may be getting weak

 

[Oil Burner]

I would guess that he doesn't have the pump on the block if he has the 95gph FASS. I could be wrong, though.



I'm thinking maybe something in the fuel pickup in the tank. I gutted mine and intalled a 1/2" pickup when my fuel level sender failed. Before I did that, I used to get some odd readings also on my old 24 valve.



I know that the 150gph pump recommends upgrading the pickup but the 95gph pump doesn't.



Anything special about your fuel that we should know about in Norway?



Jason

 

[LKjernasen]

Good morning from Norway.

The original pump is bypassed and thp FASS95 is installed under the bed behind the cabin, according to instructions. . The Diesel fuel here in Norway is known to be very clean and during the wintertime they have addidtives in the diesel to prevent it from freezing,guess they have the same up in Canada and Alaska?

Yesterday i lost my fuel press completely. Had to park. 7 psi idling and 3 psi when i touched the pedal?? Bled the filter, cycled the pump, 18 psi when cycling, ok... starts up... 9 psi idling??? and nothing when i try to drive... . Right now this RAM is up for sale... cheap

 

[JSontag]

Try getting in touch with fass. They might have an idea on what is bad.

 

[Jed]

LKjernasen

Do not despair, I will buy your truck for cheap. We will have to work out the shipping thing though.

I have had a FASS for a few years and about 50,000 miles. Send a private message to Diesel Dan and he will help, if not call FASS on monday and ask to speak to Dan McDonald. He is the contact point at FASS for us.

Make sure that they know that it is an international call and it is costing you money.

I had something very similar this summer. It sounds like it may be the gauge, find a test gauge that you know works most mechanics have one. Dan had me pinch off the return line on the FASS and see if the pressure would spike. MY gauge would not move off of 0 psi so I had to drive 20 miles with gauge at 0 psi. to a test gauge. (that was a long drive!) Result was I had 19psi as always, at that point I bled the antifreeze out of my line from the isolator to the gauge and my pressure came back to 17psi on the gauge. Have had to bleed a few more time but now with no antifreeze in the gauge it holds fine.



This is not to say that you do not have a serious problem.

Before I had a gauge or mods I had a vp replaced under warrantee so do not drive it far.

By the way can you hear the pump running with the engine running?

I have to think that if you can hear it running you must have some pressure.

Most of the FASS problems I have heard about were related to the motor not the pump itself.

Hope some of this helps

jed

 

[LKjernasen]

Hi Jed.

Thanks for tips and hints, it's good to have a forum, up here Dodge is not so common... I'm outnumbered by Chevy's;-)

I'm actually into if there can be something wrong with the instrument. I have installed a Di-Pricol Optix instrument, and i also have antifreeze in the hose. I'm going to look into it this evening. And the pump is running all the time, all seems normal. Yesterday i had to move my car and the last 10 miles without press. But, if there is no fuel press, do you get some indications, like running poor, slow response to the throttle or other things, or does it just run like normal until the VP just dies?? Because I can not notice any excessive noise (besides of the regular noise from the engine... sounds like i left my toolbox under the hood... hehe) And the engine is running like normal, responses to the throttle is normal. But to be on the safe side, i will lower the tank, replace filters, check the fuel line inch by inch... and of course, check the instrument. It's getting colder up here, this morning it was 10 below zero F and dropping... .

 

[Jed]

Thanks for tips and hints, it's good to have a forum, up here Dodge is not so common... I'm outnumbered by Chevy's;-)

I'm actually into if there can be something wrong with the instrument. I have installed a Di-Pricol Optix instrument, and i also have antifreeze in the hose. I'm going to look into it this evening. And the pump is running all the time, all seems normal. Yesterday i had to move my car and the last 10 miles without press. But, if there is no fuel press, do you get some indications, like running poor, slow response to the throttle or other things, or does it just run like normal until the VP just dies?? Because I can not notice any excessive noise (besides of the regular noise from the engine... sounds like i left my toolbox under the hood... hehe) And the engine is running like normal, responses to the throttle is normal. But to be on the safe side, i will lower the tank, replace filters, check the fuel line inch by inch... and of course, check the instrument. It's getting colder up here, this morning it was 10 below zero F and dropping



Try burping the line from the isolator to the gauge

With 0 fuel pressure it should not run very well, hard to start, no power ect...

find a test gauge

jed

 

[Jed]

Is it possible that it is cold enough to cause the antifreeze in the gauge to thicken up?

 

[LKjernasen]

Regarding the antifreeze thicken... well... i'm not sure. The mixture is proof down to -58 F, and if it's getting colder, i will for sure stay home and feed my fireplace

I will look into it now, i'm getting back with updates when i'm done.

By the way, it's 12 F below now and i had no problem starting, without block heater.

 

[LKjernasen]

PROBLEM SOLVED!!! It appeared to be the isolator!! I disconnected the isolator and connected the instrument directly to the outlet on the fuel filter... and... viola... i got 17 psi idling and 14 wot... i am happy But, before that, I disconnected the hose between the fuel filter and the isolator, while the pump was cycling... . and I tell you guys... a FASS95 delivers a LOT of fuel, I had diesel all over me and the car, and the car next to me So, a new isolator and case closed.