Quote Originally Posted by stackz View Post
I have my 88 truck harness almost sorted. kinda confused on two connectors over by the fuel pump relay.

I believe the one is the fuel pump test connection?
20240312_143311.jpg
two prong and has tan/white and a pink/black. both end up at "junctions" in the harness itself. which branch out in various ways.

its weird to me that on one side it would be "fuel pump signal" as per terminal B2 on the ecu connector and then "ign - ecm fuse" as per terminal A6 on the other ecu connector.

what do I even do with this thing? was it ever connected to anything? can I cut it out?

http://www.gearhead-efi.com/gearhead...ng/747ecm1.jpg
http://www.gearhead-efi.com/gearhead...ng/747ecm2.jpg
The ECM needs to know when the fuel pump is "On" / "Fuel Pump Signal" The wiring for the "Fuel Pump Signal" is spliced into the power wire going to the fuel pump.