Injector and alternator wiring question

[gmachinz]

Jp, I don't see an issue running your excitor lead off your injector harness-if the alternator excitor lead power is shut off (I assume by ignition, off...) then there isn't any way it could drain the battery through that circuit. As for feedback or the possibility of any current travelling back through to your injector harness, use a tamping diode between the harness and the alternator lead-this way, the current can only travel in one direction and and feedback won't be an issue for you. Just for the sake of simplicity, why not just run a relay off the ignition dedicated for the alternator excitor circuit? We're not talking about a lot of current anyway, are we? I'd leave the whole circuit out of the injector harness altogether but if you go that route, be sure to use a tamping diode inline. Curiously, what kind of alternator are you runnin', JP? A 1-wire with 3-wire features perhaps? -Jabin