EFI help needed, Wiring questions.

tanis4457 said

I've installed two Holley sniper kits (using the coil module only), the best plan of attack here is to verify which wires provide 12volt at cranking, all the time or in the run position only with a voltmeter. Then you can figure which wires you want to run to the Holley kit for the switched voltage and the on all the time 12 volt. Your probably going to end up with some wires you no longer need.

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CAREFUL it is not a hit miss "which wires verify".

THERE ARE ONLY 3 WIRES that come from the ignition switch and into the engine bay which are involved here

1 There is ONLY ONE "run" wire, normally dark blue, and "goes cold" during start

2...IGN2 the brown bypass circuit, hot ONLY in cranking. This is SEPARATE from the "start" wire to the start relay

The IGN1 and IGN2 are to be jumpered together with a non-stock ignition, which does NOT use a ballast resistor

3.. The normall yellow "crank" AND IT IS NOT TO BE USED FOR any other purpose. WHY?? Because it will cause a backfeed condition in park or neutral, and MAY even cause the starter to stay engaged in park or neutral this wire goes to the starter relay

The "unless" is that you can use a second relay off this wire, or "steering diodes" to isolate other circuits. This might be say, if an alternative ignition switch (GM or aftermarket) which does not have the IGN2 circuit