I have right now a stock lift pump on the truck getting an airdog today but for the time being here is what is going on. installed a Edge J/A and at first the key on the pressure would go to 17 psi then down to 4 psi as the pump was running (Lift pump) so we pulled the checked valve out of the VP44 and changed it still the same, we also put a mech gauge to check the edge, it was right on, so we replaced the lift pump with a new carter 12 to 13 psi key on engine off and it held, here is the thing that worrys me when you get on the truck it will drag down to around 4 psi at the lowest point on a hard pull. but most of all I dident know if there was anything in the VP44 that would let the fuel pressure drop off from 17 to 4 psi besides the check valve on the side of the pump, or anything that would cause the pruessure drop on the key on engine off beside a bad lift pump? I just got the truck makes me mad I drove it from GA to KS more then likley like this with only 4 psi on the lift pump at idle, no telling what it was going down the road. Sorry for the book.
thanks for any info