Join Date: Jan 2006
Location: Northern California
Thanked 2,626 Times in 2,117 Posts
Here's a few things to know:
There should be zero fuel pressure when the engine is not running. Any pressure remaining when the engine isnt running means there's a blockage in the fuel system.
The fuel tank should have zero vacuum or pressure in it when you open the fuel cap. If there is pressure then one or more of the injectors is bleeding pressure into the return fuel system and the fuel tank vent is plugged or capped. If there is a vacuum then the fuel tank vent is also plugged or capped. Know whether or not what you're hearing is pressure escaping or air entering.
The tank module has a flexible plastic line that moves with the tank weight from fuel. If its cracked then you'll get an air leak when the fuel level gets to that point.
It kinda sounds like you have a few things going on here...
'01 2500 Sport 4x4 5spd w/Fastcoolers, Mag-Hytec, EZ, RV275's, 4" w/o muffler, South Bend, Steering brace, aFe, 2 lo kit, Isspro Boost, FP, and EGT on pillar, Westach Trans/Diff temp gauge in dash pod, Raptor 100 w/ 1/2" line, Pac Brake, Rancho 9000, 285's