86 CJ Wiring Questions (Including MPI)

86 CJ Wiring Questions (Including MPI)


Sparks, NV
86 Cj7 4.6L Stroker, D44/D60 Airlocked, NV4500/D300.
I have an 86 CJ7 that I am rebuilding and need some help with the wiring. It has the Hesco/Mopar MPI system on a stroked 4.6 in it. I just ordered the Unichip and decided to run through the wiring on the jeep and clean it up since it has had years of being hacked on. I am assuming that some of the items on this were hooked up incorrectly over the years so I am trying to start from scratch. I have now identified all of the wires in the original harness going into the stock fuse box and want to reconnect everything.

In addition to the MPI kit, the Unichip that will be in it shortly, and the normal wiring, I do also have a Premier Powerwelder Regulator and Alternator.

I have a few questions as I am putting this back together.

1. The Blue "Start" Wire - at the firewall connector there is a block of "AX" in the wiring diagram which has two wires coming from it. One of those wires runs to the starter solenoid but the other is cut. Where did that other wire go to orginally?

2. Premier Power Alternator Regulator Brown Wire - The Premier Power Welder site shows the brown wire as being a keyed 12V power. When I unhooked this wire it was connected to the Electronic Ignition Control Feed connected to the wiring block in the firewall. Is there a special purpose for the Electronic Ignition Control Feed as that was also connected to the yellow wire in the Mopar/Hesco MPI wiring harness? Is there some other connection that should be connected to the Alternator regulator?

3. Hesco/Mopar MPI - What does the diode do in that system? Where should it be hooked into the system? I cannot find it anywhere in my system and can't tell if they left it out the MPI kit was originally installed (that was done by the previous owner).

4. Fused Ignition On Feed - What should this be connected to?

5. Ignition Feed - What should this be connected to?

6. Battery Feed - Assuming this connected directly to the battery but want to be 100% certain. Does it need to connect anywhere else?

7. Harness to Transfer Case/Tranny - I know that the orange wire connects to the 4 wheel Drive light and know that connector. There is then a White wire with a line that is for the Backup Lamp Feed and a Red wire that also goes to the plug for the original T-5 back up lamp plug. There is now a NV4500 in the jeep. Can you tell me where each of the two wires should connect on that tranny or what the purpose of the red wire is?

8. MPI Wiring Harness - The only connection I can see from the MPI harness into the original harness is a yellow wire which was connected to the Electronic Engine Control Feed. Should there be anything else connected the MPI PCM harness into the stock CJ harness?

9. Small Red Wire To Starter Solenoid - I know this will connect to the other terminal that the small blue wire does not connect to (I do not think it matters which one connects to which but please confirm if I am wrong). Where should this wire being connected in the stock harness?

10. Starter Solenoid - I have a stock style starter solenoid. I know one side of the solenoid will connect to the starter itself. The other side I believe connects directly to the battery. Please confirm that as correct.

11. Starter Solenoid #2 - On the side from the battery noted above, what else connects there? Anything need to connect there or is that just an easy connection point for other things to have constant power?

12. Fuse block Firewall Connector - on the firewall side connector for the fuse box, the connections are covered in a black tar like substance. I know it is a none conductive sealant of some sort, but does anyone know what it is called?

Thanks in advance for any help you can give.
Thanks for that, it definitely helps. I also ordered a shop manual and the CJ rebuilders guide as well. If anyone has additional thoughts on these questions I would really appreciate it. Thanks.
Have you tried the Hesco forum?

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