Quote:
Originally Posted by Ford Assassin
I have a stand alone harness with its own fuel pump relay and power wire. Any reason I can't just plug that fuel pump power wire from the LS harness into the 'test' wire on the factory TBI relay on the firewall? Trying not to butcher the factory harness, nor make more work for myself.
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Terminal D, the hot coil terminal of the fuel pump relay, was driven by the TBI ECM on Connector A Terminal 1... if the wiring diagrams are correct. I posted a snippet of the fuel pump circuit in the tech writeup.
The most elegant way to do this would be to drive the relay coil exactly like the original setup.
I'd find the original TBI ECM end of the fuel pump relay drive wire and attach it to the fuel pump drive on the LS PCM. This will offload any high current draws that might make the PCM fuel pump driver transistor unhappy.
You should be able to buzz the original ECM Connector A Terminal 1 wire to the fuel pump relay terminal D to be sure you have the correct wire.
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