Lost fuel pressure ,fuel coming out of number 6 cylinder

[big poppa pump]

1999 Mercury 300 pro max, was running down river fine, then slowed down and cut off. Pumped primer bulb up and got back end. Pulled spark plugs and checked fuel pressure -none. Pumped primer bulb tight , turn key on no fuel pressure, hear pump running ,crank motor over without spark plugs, fuel is pumping out of number 6 cylinder

[flabum1017]

may have spit the tip off that injector

[big poppa pump]

What would cause #5and #6 injector to spray fuel wide open. Motor isn't even running , key in the on position ,injectors steadily spraying

[big poppa pump]

Just had injectors clean 2months ago by brucati

[TEXAS20225]

pintel stuck open

[flabum1017]

Unplug them and see if they still keep spraying

[merccrazy]

Had a 250 3l efi years back with the same problem. The ground for 5 and 6 in the fuel ecu stuck closed. Replaced the fuel ecu all good.

[PanRonnie]

you have the promax with the laser style intake?
O ring leakage? ( fuel rail)
maybe got damaged when assembling

[demag67]

Ohm your injector harness. If you disconnected the plug for the injectors does it still lose fuel pressure . If they are good pull the front of the intake off. Either the orings for the injectorsare bad or a pintle is stuck or orings for the fuel lines are bad.

[big poppa pump]

I discounted the fuel injecter harness and it stops spraying. I'll check the harness but I got a feeling it's the fuel ecu.

[Euroski]

I discounted the fuel injecter harness and it stops spraying. I'll check the harness but I got a feeling it's the fuel ecu.

Maybe the harness is rubbed through and touching block? Like above ohm test the harness end to end and each wire to ground with ECM and injector unplugged

[native2]

I had same problem with a 300 pm. It was the fuel computer...