5.0 GXi…

[KPotter]

Hello all. Went down to the boat today to clean it up and check it out. Started and died. Multiple times. Even if I applied some throttle. Replaced the fuel filter. Old filter was full of clean fuel. Connected a pressure gauge to the high pressure side and it doesn’t register anything. Checked for power at the high pressure pump. No power. Any ideas for further diagnosis? Thanks.

 

[dubs283]

Check the relay/12 volt supply and verify good ground for the pump and relay connection

 

[alldodge]

Might also be the key switch
Do you hear a beep before cranking?

 

[KPotter]

I checked the grounds at the plugs for the fuel pumps. They are good. I do hear, well kinda, the beeps when you turn on the key and you can hear the pumps activate. I checked the power at the pump plugs and it’s not 12V, more like .04 volts. But I’m not getting any pressure at the high pressure side when I turn on the key. Not sure if it has to be running to read that pressure.

 

[dubs283]

In that case you have a voltage supply issue. Either faulty relay or 12 volt relay supply

Ecm controls the ground circuits for the relays which energize momentarily upon key on, engine off. 12 volts needs to be constant at the relay connection