I have a 2002 4.7 and overnight it loses all fuel pressure. I had a shop look at it and they put in a new fuel pump. This didn't solve the problem. Has anyone ever had this problem that could lead me into the right direction so that I don't have to take it back to the guys who incorrectly guessed the first time. I appreciate any help. Thanks.

(Does anyone know exactly what is involved in the fuel system. I know fuel pump, inlet line, fuel rail, and injectors. But is there any other part of the equation I don't know of. I do know there's no fuel pressure regulator.)

 

There should be a check valve in there and my guess is that it is not seating correctly allowoing the fuel to go back to the lowest point (gas tank). We're actually going over this in my diesel class right now and that is the common reason for loss of pressure after shutdown.

 

I was told the valve was part of the fuel pump...so now I'm confused. Is this thing your talking about seperate from the pump?

 

get the FSM for the 2002 durangoat here, the fuel section is explained in detail
https://dodgeforum.com/m_979861/tm.htm

 

the valve is part of the pump assembly, when you turn the key on you should hear the pump turn on for 2 sec to pressurize the fuel lines... check that 1st and let us know what you get. you should also slap a fuel pressure gauge on the rail to see how fast the pressure comes up.