Fuel pump circuit 2012 2.7

So I blew up the original engine at 166,000. Replaced with a junkyard engine 178,000 and threw a p1604. I wasn't getting fuel to the rail. Dropped the tank and replaced the fuel pump. Getting voltage but no current to the fuel pump connector. Finally got her to start and run jumping power from the c/opn relay to the back probed fuel pump. Could I still be chasing ecm issues or am I down to an open circuit between the relay and the fuel pump?

 

Hopefully some can chime but what happened to and where is the original motor? New valve cover gasket on replacement engine?

 

What year is your truck?

Whay do you mean by you have voltage but not current at the fuel pump?

The P1604 (Startability Malfunction) is just a Toyota generic code that means the engine failed to start or started and stalled, doesn't really mean anything beyond that.

 

Old engine is on a stand. Cam phaser grenaded. Negative on the new valve cover gasket until I can prove the junkyard engine is worth keeping in. Was reading 11v at the pump connector but couldn't get a test light to light up.

 

So it sounds like you have a voltage drop (poor connection) on the fuel pump circuit, I'd check Connector IB1 Pin 8 (Black/Red). Not uncommon for that pin to get burnt and lose connection.