Wondering if anyone has installed the bushing to keep the rails with fuel. I'm looking tio see if it will keep mine from throwing the rail code in level 6 with the edge.

Mine does the same in level 5. Guess we will have to get us lift pumps????:(

I have a fass and twin cp3's and it still throws the low rail pressure code:mad:

You could try a shim but you might be better off installing a PPE or other lift pump

AIRDOG same as fass just half the price

Lift pump will not sovle the problem you will need to shim it.

racevalve and lift pump

Again I have the race valve, lift pumps, and twin cp3's and I still get the low pressure code:mad:

:D I got a raptor 150 to fix my problem.

Again I have the race valve, lift pumps, and twin cp3's and I still get the low pressure code:mad:


that doesnt make sense, it sounds like in theory you would have enough fuel psi and your rail pressure sensor would be malfunctioning or something

I'm open to any ideas that anyone has. I would think that if my stock cp3 was going bad that the Twin would pick up the slack but what do I know:rolleyes: I'm running outta bolt ons that "should" fix my problem:mad:

As I understand it, I thought that each cp3 only supplied fuel to each rail separately (stock pump to p-side rail, and 2nd pump to d-side rail) I could be wrong. Have you done a bottle test to see if it is going back to the tank? How low is the pressure when you log it? I have not installed this on my LBZ but have on an 05 LLY not to bad just tight.

sounds like it is in your tune?

It did it before I ever put a tune on it. First time it did it I was hauling a skid steer going up grade. Truck only had 4k on it and no mods:eek: not even a strait pipe:eek::eek:

I have been having lots of rail presure issues also. I have 2 trucks a 06 and a 07 classic. The 07 is the problem child I have switched modules back and forth and nothing changes. The 06 will smoke like crazy and makes a ton of power. So I took a tech 2 out for some data and just as I thought it runs right out of fuel. So the dealer put a new high pressure relief valve in and didnt fix it so they will be putting a new pump on it this week.

So I thoght I would do a little testing first i tore the tank out to see the pathetic pick up set up Gm uses and I modified it and this helps some on the presure. Next I took and put in a Mallory 250gpm billet race pump in the system I put a direct pick up on the bottom of the tank and plumed it in the sytem with valve to turn it off if need be. To my big surprise the lift pump makes it worse alot worse!!!! So I took the pump off and took the pick up and plumbed it in so it has 2 pick ups out of the tank this seems to have made the best improvement it does not throw the code nearly as often. I will update after I get the new pump on.

One last thing there is a bulletin that if there is and crap in the fittings any where to replace the pump and the guy I now at the dealership also said he has replaced several pumps on trucks that sat on the lot a long time before they were sold.

Just curious if the bottle test has been performed?

Smitty your lift pump was putting out way too much pressure I believe. You only need like 12-14 psi. That pump sounds a lot hotter!

The pump has a bypass return built into it and is set at 15psi.

http://www.puredieselpower.com/catalog/04507-chevygm-66l-lly-lbz-duramax-race-fuel-valve-p-817.html
good cheap add on??

I'd check the Fpr. It can cause those codes aswell.

do any of you that are having this trouble have the valve shimed or a racevalve installed i had this problem shimed it it got better then i got hotter and then it started doing it again and i put a race valve in and it hasnt done it since

I had the problem on the stock fuel system, I installed a lift pump and a shim with all 3 washers, Haven't had it happen yet, gunna try to log it at the strip tonight and see what the pressure is doin. Hopin for a mid 12 :D

Thanks for all the input, I have ordered a shim and 4" exahust turboe back. I am interested to see what difference this will make.

def. on the shim and lift pump, but mine did it even after up until efilive which seemed to make it dissapear.

I'm using EFI Live and I still get the code and I have twin lift pumps and hope to soon be getting twin cp3's and a mitusa belt driven lift pump from opie parts. Which should hold more fuel to the rail and injection pump than I ever need cause with all the lift pumps combined I'll be flowing close to 395gph and practially all the pressure I can turn the belt pump up to. And the twin cp3 should be more than happy with the constant supply of fuel, problem being if thats not enough I don't know what is.

I may be crazy but I changed like 5 different tables or so, and the codes do not pop up. I say shim and lift pump at a minimum.