Hi, I have a couple of questions about wiring (see attached photo)? 1. what does the single red wire coming off the wiring harness connect to? 2. The other connector in the photo has three wires. I know one goes to the temp sensor, one goes to the oil pressure sensor but where does the third red wire connect to. I'm asking because I need to complete my hookups from the MSD 6AL module. The wiring diagram says to connect the red wire to the ignition switch. I have the same question for the electric fuel pump. One wire (10 gauge) connects to the battery. Another wire (yellow)runs through a relay and then on to the ignition switch. Someone suggested that I connect the yellow wire to the "ignition" terminal post on the starter but there is already a jumper wire connecting the starters battery post and the ignition post. I'm wondering if one of the wires in the photo would work for both the MSD and the fuel pump. Not sure if it matters but I'm also using a single wire alternator.
Hello The Wire that says coil does in fact go to the coil, and the single red wire on the other connector is your fast idle wire i believe. does your MSD box say it needs to be hooked up to a 12 volt source, if so you will need to bypass that coil wire as it is a resistive wire and drops the voltage down to around 6 volts
Yep that red wire with ? feeds coil, the single wire does nothing, has no connection that I can find(at least on my comet)... Fast idle is fed from a wire in A/C harness... Assuming you're powering MSD unit from battery and coil is fed from MSD, you can use the red wire to activate it(resistance wire makes no difference, no voltage drop without load)... Other than fuel pump relay coil, do not connect anything else to the circuit... Disconnect I terminal on solenoid, isn't used with MSD...
Thank you. Now I can finish the MSD wiring with some piece of mind. What about the electric fuel pump? I have a red 10 gauge already run to the battery but there is another smaller gauge wire that needs to go to the ignition switch. Can this also connect to the red ignition switch coil wire?
