Hey all, I did a little digging but I couldn’t find anything that really covers my predicament. Just came back from a three year tour over in good old J-pan and picked up a 90 FC. The guy I bought it from had it built by a shop in Hiroshima and I mean, it runs but the wiring is janky as all hell. Currently running a powerFC and I’m curious as to how I should go about fixing some of this mess, do I just pony up the cash and get a full new harness or try and trace all the unlabeled wires throughout my engine bay/ cabin? TIA!

any recommendations? Not too savvy with electrical work

Correct me if I’m wrong please.

Im running a usdm s5 engine harness on a power fc (installed myself 4 years ago when I did my turbo swap) but I barely had to do anything. I did disconnect the aws and that other thing plugged into a usdm upper intake manifold, and maybe disconnected one of the two connectors on the acv, but that’s it. The points I just made are due to usdm emissions which did not come on jdm engines. So just get a new harness. Do your research but t should be as simple as taking out the old one and putting in a replacement.

Your recommendation, just as he said. Get a replacement harness. If you love the car with every bone in your body, find a new harness. If a hair less than that, just find a low mileage harness. S5 n/a will work on t2. Use the search function and extend the tps wires and change the wiring for the boost control solenoid. Good luck

just added this. You never mentioned which power fc you have. If it’s a Fd Power fc it makes sense why the wiring looks jank.

Im running a FD power fc with a banzai racing patch harness that allows me to run a s5 harness with 0 issues. This might be the key

Honestly I have no clue, I don’t know very much about the car at all unfortunately.. if it’s not in Japanese it’s not labeled. When I asked around to a few Japanese friend they just kinda of shrugged it off and said “that’s just how Mukai does it”