I have read on here that a few people are finding that their fuel pressure is dropping to 0 while under hard acceleration even with very mild power adders.

My question is have the lift pumps changed between the 04.5 600 series to the 06 and even 07 600 series engines? I thought that I read that the 06 and newer trucks have a lift pump located in the tank for better durability and fuel flow. Is this correct or am I on drugs? Some insight will be apprecaited.

-Jeremy

 

Starting in the 05 models they went to in tank. The average flow is 9psi. This will not support many of the boxes out there. You will loose pressure and possibly injure the CP3. My intank would go from 9-0 in about 3 seconds on the quad race box.

 

That is what I thought but is the in tank better than the external unit or is it just different? I have the XZT coming and I do not beat on my truck but I do pull around 10,000 lbs 4-6 times a year through the mtns and do not want to starve the CP3 while pulling some of the steeper grades.

I would prefer to leave the fuel system stock because my dealer has told me that tampering with the fuel system is much harder to get around with any warranty issues than installing a power adder because the power adder can be removed and the fuel mods are permenant. One thing is for sure is that I will definately be getting the fuel and rail pressure sensors for the commander.

-Jeremy

 

With the Smarty and Quad both set on kill the fuel pressure drops to just below 4psi - bone stock fuel supply system.

 

You'll be fine with the factory pump. The in-tank pumps seem to work better and last longer than the engine mounted. These pumps like to push the fuel more than pull the fuel. I have the Quad Std. module and tow 10,000 lbs and towing on the 60 h.p. setting I've never lowered fuel pressure more than a couple p.s.i.

 

I can concur to the previous posts, however on my truck the Quad race will pull the stock pump to 0psi on level 3 in about 3 seconds. I think you should be fine, just hook up the new box and give her a test run. Watch your fuel gauge and if you are dropping below 3-4 psi for any length of time, you need to upgrade.