Hello all, I am in the middle of rewiring my 1986 F150 with the 5.0. I have taken a 1991 Ford Mustang mass air flow harness and integrated it into my truck. I need to find my ignition run and start wires. I have included pictures of the two connectors.


Can someone please tell me what each wire is for.

 

that plugs into the box on the fender well in front of the MC and booster

 

Red with a lightblue stripe will be the start wire to crank it over. White with a lightblue stripe will be your raw 12v in run wire. Get a meter and check them to be sure, the colors are hard to make out after so many years under the hood.

 

Starting with the 4 wire plug...
The Fat wire is the feed for the coil positive, both run and start, but this is downstream of the resistor wire so you might need to use this to trigger a relay. What type of ignition system are you going to use?
One is a Key ON 12 volt source that you might not need.
One is oil temp
One is water temp

The other 3 wire connector is meant to plug into a DS2 ignition module.

Jim

Jim

 

I am running the EEC IV ignition system. I am planning on using relays but I'm trying to figure out which wire's are my run and start for my TFI and coil and then still have to figure out my power wire for the relay .