First of all, I am new to this forum and still trying to figger out how to post and answer. If I fail to respond or to thank any poster for help received I apologize. No attempt to be rude to anyone.

My 98' Dodge has 192K and dont drive it very much now days since retirement. I only drove it eleven hundred miles in the last four years. I recently broke down and had to be towed to a repair facility. Replaced VP44 and factory lift, cost $2800. They really ripped me. I know very little of the newer Dodge diesels as my old Dodge 1990 was pretty much bullet proof. I am trying to set up the fuel system to be pretty much Bulletproof aswell. I started by ordering a Isspro EV2 Fuel Pressure Guage. Next will be a Raptor 150 lift pump and then fuel tank issues and Injectors. Tom

 

ok now my nfuel pressure gauge all of a sudden tonight is messed up when i turn the truck on the fuel gauge is maxed out to 30 psi and then when i rev it up it goes down to 15 but then when i let off it jumps back up to 30 again what could be wrong?

 

in what truck are you referring to? from what I have been told the in tank pump will not work with another lift pump unless the intank is still working.

 

I have an '07 with the factory in-tank pump (not the one in my avatar, the 1st one in my sig). Here's a pic of the pump installed that pulls just fine through the in-tank. And it ain't no big honkin' mondo overkill Air Dog, either. As you can see, it's plumbed in series right into the stock line:

http://stuff.is-a-geek.net/PhotoAlbu...ics/CRD_27.JPG

It serves a backup and helper pump in my application. It works fine all by itself as a backup, tested by disconnecting the connector on top of the tank. If the in-tank ever fails, no worries. That Walbro is normally wired to a relay from the water-meth hobbes switch to activate under high load and boost fuel pressure under load. The low side fuel pressure on that truck actually rises from a nominal 10psi to 12-15psi at WOT.

 

Ive seen people kill Airdog's and FASS systems by trying to pull fuel thought the intank pump.

 

but in this application your not relying on just the pump to pull fuel out of the in tank pump and pump it. change up the application and watch it kill your pump. the in tank is not meant for that and doesn't flow enough and burns up pumps.

 

I drove it like that for a 2 week test after I first installed the Walbro. So, yes I am/can

One reason engineering elected going to an in-tank FLOW-THROUGH pump was to mitigate damage to the injection pump in the event of LP failure. It allows the truck to run without the LP and without damaging the CP3. That's what killed all the VP44s - the stupid engine mounted NON-FLOW-THROUGH LP.
Cause and effect? Or wild-assed guess? I've see FASS and AD's die all by themselves...

 

thus is also a design that only works with a cp3 as a duramax doesn't run a lift pump with theirs. a vp can draw it's own fuel through a dead lift pump, but really only enough to idle without over heating it. a vp is not like a cp3 and dies trying to push and pull it's own fuel. 2 weeks not a very long time, it may work, but would not trust it for a long period of time. Just been through this with a few buddies trucks.

 

I'm talking about whether or not the LP is a flow-through design or not. The engine mounted pumps on the early 24Vs was not. The in-tank pump is. It is also extremely reliable compared to a FASS or similar setup primarily because it lives in the tank where it stays cool.

I don't have to trust anything - I use a post filter fuel pressure gauge. No trust issues whatsoever.

 

I guess you need to read up on the issues of in tank pumps for the 2nd gen 24v's then. the in tank pump is just as bad if not worse than the factory on the block lift pump. The 3 people I know that had the in tank pump done to their truck all had them go out within 1 year from date of install. All 3 now have a fass for the last 3 years with 0 issues. Maybe the 3rd gen setup is better, but they still bypass them in favor of a fass when making more power.