I have a 2004 duramax that i reciently changed the fuel line that goes from my fuel sending unit to my steel feed line.. I also replaced my fuel filter housing because the truck was loosing prime.. I primed the fuel filter without the bleeder screw in and it filled the filter as it is supposed to... Put the bleeder screw back in and tried to start the truck but it wont start.. I left it overnight fully primed and in the morning i checked it and it remained fully primed so it appears that no air leak is present...Iv been told once you have filled the filter (with NO bubbles coming out of the air screw)you put the bleeder screw back in, pumping the filter housing with the screw in can damage the housing, therefore i have not pumped it with the bleeder screw in.... My old damaged housing i have primed with the bleeder screw in, and the truck idles fine but when i go out on the highway it goes into a limp mode where there is a significant loss in power(assuming the housing is the reason) Why wont it start with the new housing!?