Well, That's an issue.

So. I've been having trouble with the car running going from running fine to running lean for a bit now and it finally got to the point where is was always running lean. Now I can barely get the car to move. After checking and replacing a bunch of sensors and changing a few things around, nothing changed. One day for shits and giggles I popped the cover on my ECU and saw a burned spot and a little black thing melted. Popped the cover on my spare, same issue. I traced it as best as I could and I think it goes to the ECU Relay pin. I think. Either way, I decided to pull the harness and the wiring I did, unwrap and check it all.

I haven't had time to check what I did, but I pilfered through the stock harness last night and it was a nightmare. I noticed it had been messed with some when I got it. It had those lovely blue crimp splice things on it. After unwrapping it, I found 1 section that is a little toasty and brown and down near the ECU plug its a total mess. Ground wire were left exposed, a couple wires were cut and missing (not from me). A bunch of grounds were crimped together then taped up, don't know what that is about.

Basically, I dunno where to start or what to do. Do I attempt to repair this harness, try to find a new one? Maybe I'm just frazzled by the crazy mess of wires and just need moral support lol. I dunno even know if any of it is my actual issue, surely its not good either way. I also need to figure out what to do about the ECUs, are they repairable? Scrap it and toss in a old 350? Barely any wiring needed for that lol. All I know is I miss my S12.

Buy a new harness. Mine (in a red MkII, I might add) has a fucked up harness I tried to repair, but it was fucked up beyond where I felt like fixing it. WiringSpecialties has premade CADET harnesses.

SchizophrenicMC on 01:46:49 PM / 01-Dec-11Buy a new harness. Mine (in a red MkII, I might add) has a fucked up harness I tried to repair, but it was fucked up beyond where I felt like fixing it. WiringSpecialties has premade CADET harnesses.

It's an S13 harness, but 99% of CA18DETs are from S13s, so the S13-S12 conversion is the same. I mean, unless somehow he got his hands on an S12 CA18DET. Then, not much I can do but say, either fix your harness or convert the new one.

well yeah but what i mean is that isn't it a KA to CA harness rather than an OEM S13 CA18DET harness?

As far as I know, the JDM 180SX and USDM 240SX body harnesses are the same, so the interfaces between them and their respective engine harnesses are, too. But I haven't looked too much.

if that was true, then CA18DET as well SR20DET swaps would all plug right in which is not the case. So they must not in fact be the same. Wiring Specialties sells plug-n-play conversion harnesses for SR/CA/RB swaps.

If you want an OEM CA18DET harness, search on other S-Chassis forums and/or call some importers.

Well, you have only 2 options, just saying.

That's it. I'm pulling out my det parts bin and taking apart my harness tomorrow. You guys are starting to fuck with my head lol. Going to start have s12 nightmares in my sleep

just try to work with your harness man nothing is impossible. if you do get the wiringspecialties harness you will still have to hook it to relays than to the s12 ca20e harness. so either way it involves work guys. just try your best. goodluck with it man!

Alright now what about the ecu? Can they be repaired or is it done?

I know I have the ability to fix the harness, it's just scary cause there's just so much going on at once. Whenever I look at it, I have no idea where to start.

If you've burned your ECU, it's time to get a new one.

And yeah, I know what you mean. I'm smart enough to wire that harness, but it's fuckin' everywhere. Pull it apart, do it from scratch. ImpactBlue has the diagram, and how it relates to an S13. Compare to your S12 engine bay schematic. Godspeed.

hey man i have a ca18det harness uncut inbox me

The real question is, did he get it before or after he sold me the S12? The world may never know.

:P