Putting an S14 KA into an S13... In need of wiring help!

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Akuhyo
Posts: 15
Joined: Fri Jan 08, 2021 7:43 am
Car: 1990 Nissan 240SX Hatch

Putting an S14 KA into an S13... In need of wiring help!

Postby Akuhyo » Fri Jan 08, 2021 12:20 pm

Okay, let me explain my situation first.

I have rebuilt a 1996 S14 KA24DE, and I am going to put my KA into my 1990 S13 hatch. I've read online, (trust me I've been researching a lot recently) and a lot of people are using the S13 KA engine wiring harness on the S14 KA, which requires to change your manifold and distributor. I already have an S14 ECU & S14 wiring harness, and I want to make this work with the S14 wiring harness which I know is possible.

I've only seen people do this once or twice, the most helpful thread was this thread: (even though he was putting an S14 SR into an S13, it was basically the same scenario)
https://www.nicoclub.com/archives/s14-s ... -swap.html

Now, getting power to the S13 dash and getting the tach to work and speedo to work sounds like cake to me, just buy the corresponding dash plug and splice the wires out of the S14 F3 dash plug which correspond to the right pinout- and voila. Dash seems really easy to wire up. :bowrofl:

Well, my problem is getting power to the ECU itself. I cannot find information on how the S14 ECU gets power, I believe it's through the dash? Let me know on that. Yet I do understand that the S13 ECU gets power through the engine harness from 2 plugs near the battery, an 8 pin gray plug and 8 pin brown plug. I bought a bunch of wire and bought 2 sets of 8 pin connectors (male & female), and I'm planning on cutting the two gray and brown plugs and putting my own 8 pin plugs on there. (Since I cannot find the corresponding plugs online)

I was then planning on extending wires from the S14 F3 dash plug which correspond to the pins on the gray & brown plugs, and just connecting them. But then of course, I wouldn't be using all the pins since I know things are different.

From looking at the S14 SR in an S13 guide I linked, it seems that the person followed those wires which connect to the gray & brown plug back to the interior and just cut those wires, and soldered the corresponding wires from the S14 F3 dash plug onto those. These are the given instructions:

- Solder black/red wire from F3 dash plug onto black/red wire on gray plug (Ignition, I checked and I do have this wire)
- Solder red wire from ECU relay on harness onto red wire on gray plug (Apparently it's the ECU Backup Power, I do have this wire)
- Solder green/orange wire from F3 dash plug onto green/orange from the brown plug. (Neutral switch, I do have this wire.)

Then there's these two, which I only have one B/Y wire coming out of my F3 dash plug:

- Solder black/yellow wire from F3 dash plug pin 23 onto black/yellow wire on brown plug. (IAC Power)
- Solder black/yellow wire from F3 dash plug pin 30 onto black/pink wire on brown plug. (Fuel Pump Relay)

I'm also pretty confused with one thing, how come the pin for the actual ECU Power on the gray plug isn't being used or soldered to any wire? Is it just going to run off of the backup power pin?

How should I manage on wiring this up? I really want to get this car running, thank you for any help! I've been researching for so long and I'm just stuck on this! I want to get it done. :tisk:


User avatar
NukeKS14
Posts: 189
Joined: Wed Apr 10, 2019 2:50 pm
Car: 1995 240SX SE - KA24DE-T
2014 Camaro SS 1LE

Re: Putting an S14 KA into an S13... In need of wiring help!

Postby NukeKS14 » Sat Jan 09, 2021 8:13 am

I've performed this swap on one of my old hatches. Most people use the S13 components because its honestly just 1000x easier. There are a fair amount of differences between the S13 and S14 components. I've heard of people running their KA off of SR and DSM ECU and wiring harnesses too but you're going to be putting the time in yourself to dig through the wiring diagrams and sort it out yourself because you're determined to be unique. If you're dead set so be it, The FSMs have all of the info you need to convert wiring. http://www.nicoclub.com/archives/use-ni ... abase.html

S14 EC wiring;
Image

Image

There is your S14 ECU power circuit. And you're not going to be able to use the SR wiring diagrams to wire your KA so just chuck that stuff right now. You are going to have to sit down with the S13 FSM for your car and the S14 EC section for your wiring harness and align the pinouts to where everything interfaces with the chassis.

Akuhyo
Posts: 15
Joined: Fri Jan 08, 2021 7:43 am
Car: 1990 Nissan 240SX Hatch

Re: Putting an S14 KA into an S13... In need of wiring help!

Postby Akuhyo » Sat Jan 09, 2021 10:11 pm

NukeKS14 wrote:
Sat Jan 09, 2021 8:13 am
And you're not going to be able to use the SR wiring diagrams to wire your KA so just chuck that stuff right now. You are going to have to sit down with the S13 FSM for your car and the S14 EC section for your wiring harness and align the pinouts to where everything interfaces with the chassis.
Thank you for your input!

But, as far as specific wires from my F3 dash plug being soldered/connected onto some of the wires on the gray or brown plug goes, is this all I technically have to do?:

- Connect red ECU backup power wire on F3 dash plug to the S13 chassis ECU backup power wire
- Connect fuel pump relay & IACV wire on F3 dash plug to the S13 chassis
- Connect ignition switch wire on F3 dash plug to the S13 chassis
- Get power to sensors

If that's all I really have to do, that doesn't seem too hard. I'm gonna print out the S13 harness section, already have my S14 harness section printed out.

Also, I'm assuming it's okay to run the ECU off of the backup power?

Thanks.


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