I have an 01 with K&N intake and superchips micro tuner as far as I know everything else is stock. I just installed fuel pressure, egt , and boost guages today. my fuel pressure at idle is 13psi and varies from 8-12 with normal driving, but when I jump on it (wot) for any length of time it rapidly falls to 4psi and goes as low as 3.5psi. I jnstalled a -3an tee in the short section of rubber hose between the filter and the IP to attach my fuel pressure line to my guage. Is my LP going bad or is the tee a retriction there? ID of tee is pretty much the same as the steel line.

 

I replaced my lift pump before it got that low.

 

I would say that your lift pump is getting weak. Keep one in the truck and when it craps out you can change it on the side of the road with a 13mm wrench and a 17mm wrench.

 

WOW!!! I was getting ready to post the same question, with the comp off the fuel pressure gets to around 8psi at the lowest, but on level 2 I see around 6psi, on level 5 it will get in the 2-3psi range. So im going to have dodge do a test on the LP to see if its bad or if it is my gauge, because I have an electrical fuel pressure gauge and I've heard bad things about them so im not for sure. About how much does a new LP cost?

 

Depends on where you buy but Iv'e seen anywhere from $150-200. My tuner is set on HP I'll have to try it on different settings to see if it changes.

 

cheapest one I've seen is Here

 

Don't waste any time and/or money going to DC for their silly LP test.......you already have all the info you need to know that tells you your LP is smoked and needs to be replaced. Knowing them, they will tell you your LP is fine!

 

I'm dealing with all this right now. Unfortunately I didn't have gauges to let me know things were going bad.
My diesel shop tells me that the low fuel pressure problem is an inherent problem with the Dodge/Cummins set up. Doesn't matter if the lift pump is going or new, at load, ie: WOT or pulling a hill, your fuel pressure will drop low enough to put the injector pump at risk.
Cummins knew about it and fixed the problem in the non-Dodge applications. Chrysler is just dancing around the problem....unless you have an 04 or newer. You get a relocation kit under warrenty.
Along with my new injector pump , they are also installing the FASS system to hopefully eliminate the low fuel pressure problem.

 

I went and had mine checked out a few weeks ago because my gauge was also reading low and I wanted to make sure that it wasn't the gauge. The gauge was reading right so I had three options, a new lift pump and FASS system with filters or just the FASS pump. Of course they didn't have just the pump in stock because it was cheaper so I got the whole kit for $630. I know it is a little more then I could buy one for but I would have had to wait for it, but I did install it myself . So you could go and have it checked out just to make sure. If it is bad you could buy the kit and install it.
I now have a spare gauge to test with just to make sure .

 

So If my problem is my LP what is the best way to go about fixing the problem? Should I just put on a stock LP and call it good for my everyday use or is there something a little better I can do that won't break the bank?

 

You could go either way. It's a fact that lift pumps will go bad. The other systems, like the FASS, Holly, etc are suppose to last longer and give you more constant pressure. I just put a FASS in, so I guess I'll find out.

 

Apparently everyone is doing the FASS system. The shop called to get me one Friday and were told they are back-ordered for a month.

I need my truck now so we are going with the Air Dog system.