Hey so I noticed that my low fuel pressure sensor light is flickering now. Both the full pump and lift pump were done last year . When I turn my key without starting the truck it flashes ( should it be doing that ?) And when I start it it dose npthing. It doesn't start too flicker till I stand on it. More less when the truck is coldish... but even when I do there is no loss of power, it doesn't cut out at all nothing changes. Should it be doing this ? Can someone let me know what's going on

 

The injection pumps in our truck need fuel pressure. At least 14psi, if I remember right, so that there is enough excess fuel to lubricate and cool the electronically-controlled pump. On startup, you only need 7psi, so I would imagine that your little light is probably set to either 10 or 15psi. When it dips below that preset pressure (which it will do if you go wide open), the light will illuminate. As long as it's not on all the time, it's nothing to worry about. You should get a fuel pressure gauge, though. It's really nice to know your readings. It's preventative maintenance against VP44 failure. I would advise against WOT until you upgrade your lift pump.

 

Yes it should be on when key is on position but not running. What lift pump was put in? what low fuel pressure kit is it? bd's comes on at 5 or lower psi. A gauge will be better so you know the actually pressure. i run mine at 19 idle and it'll dip down to 13ish at wot.

 

At 14psi, the return valve shuts of within the VP44 and you run the risk of overheating the internals.