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The EFI-1 fuse powers a few components. If the fuse blows all the time then the short is constantly present now which will make it much easier to diagnose. The fact that the short doesn't appear until the key is turned on tells us that it is likely happening on a relay output circuit, the ECM waking up with the key on is turning on a couple relays in the circuit and the short is most likely on a relay output circuit.
One branch of this circuit leaves the fuse and goes to the ECM. Unplug the ECM and see if the short goes away, if it does then the problem is the ECM.
The fuse also powers the EFI relay which then powers many different components. From the EFI relay it also powers the fuel pump relay, and then to two more ECM circuits. Remove the fuel pump relay and see if the short goes away, if it does then the problem is the pump or it's wiring.
If the short is still there with the fuel pump relay out then remove the EFI relay and see if it goes away. If so then the problem is between the relay and ECM or the ECM itself.
Thanks for your reply. I pulled the Fuel Pump Relay, turned the ignition key and the fuse did not blow. I tested the relay for continuity and it failed. I bought a new relay and replaced the fuse. The car started and I drove it for a few miles, but then the fuse blew again. I bought a 2nd relay and replaced the fuse but this time the fuse keeps blowing. I am suspecting the fuel pump or a short in the fuel pump circuit. Ideas?
Thank you. I will try that tonight