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Discussion Starter · #1 ·
Hey everybody as you can read from the title i have just swapped an 83 engine into an 80 body, someone had previously sold the engine and i could only find the 83 ecu engine and harness so i decided to put that in it.

Now for the questions,

Currently i have the 83 automatic ecu in the car, i have a manual transmission in the 80 body (dont think is a problem) and have no idea where the power wire for the ecu comes from, currently i have two sub harnesses hanging over the passenger fender (one from the 80 and one from the 83) and i dont know which wires to join or cut or what not. I read previously that it is basically the same harness and such but i have absolutely no clue where the ecu gets power from. I have read diagrams saying it runs from the battery to an inline then right to the ECU, if someone can give me a color-coded diagram or give any insight thatd be great!
 

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You can get wiring diagrams and electrical information from the FSM (factory service manual) and you can download it from www.xenonzcar.com for free.
I wouldn't do any cutting or anything. The ecu doesn't care what transmission is in the car (at least on the 280zx), its really just for fuel management. I would just use the 83 harness, with the 83 ecu, with the 83 powerplant.

Bon
 
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Discussion Starter · #3 ·
You can get wiring diagrams and electrical information from the FSM (factory service manual) and you can download it from www.xenonzcar.com for free.
I wouldn't do any cutting or anything. The ecu doesn't care what transmission is in the car (at least on the 280zx), its really just for fuel management. I would just use the 83 harness, with the 83 ecu, with the 83 powerplant.

Bon
Hey thanks for the response! I already have those wiring diagrams but sadly they arent color coded so i have no idea which one of the wires in the harness to wire to the battery, what i am probably gonna end up doing is just completely doing my own separates inlinefuse box but that brings me to another question. Is the inline fuse box in the engine next to the battery the same on both cars? If so i can just wire it up to that, or i could just have 2 boxes (83 harness for engine and ecu, and the other one for the 80 harnesses)
 

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hmmmm. Well, you could try one of the old Clymer manuals. I saw one on ebay for the 280zx. It might have color coded diagrams.
I'm not sure about the fuse box. You mean the fusable links? Probably not a good idea to mess with those. You would have the read up in the electrical section on both cars (80 and 83) and compare the differences if any.
 

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I would do away with the entire ECU and ECU harness and go with a plug-and-play system from Godzilla Raceworks. I did, and my 81 Turbo runs so much better. My 81 Turbo used to be an automatic (because there were no five speeds in 81 for the Turbo). The car now has the entire drivetrain from an 82 turbo (Rebuilt Engine, 5 Speed BW tranny, rear end, and CV Axles). I put the Godzilla Megasquirt system on, and the car starts every time. All previous ECU wiring has been removed to not confuse things. It is much cleaner and neater in the engine bay.
 

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Discussion Starter · #6 ·
Hey monty thanks for the response, sadly mine is not a turbo and their ecu harness will not work, also i am 95% there and don't have the budget to convert the whole system and go through that mess, thanks though!
 

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Hey monty thanks for the response, sadly mine is not a turbo and their ecu harness will not work, also i am 95% there and don't have the budget to convert the whole system and go through that mess, thanks though!
I get it. I just know how bad that wiring can be after 42 years. Good luck and keep that megasquirt system in mind. That being said, did you try "The Z Store"? They had some rebuilt ECUs for a little while. Also, try "the Z Man of Washington" he specializes in S130s. Last bit. Try Todd Wagner out of Virginia or the Carolinas. He is very familiar with the issues associated with S130s.
 

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On the 1983 the power comes in at pin 27 from the EFI relay when the ignition switch is in the run position. Plus pin 17 gets power from one of the fusable links, this also feeds + to the injectors. The 1980 is similar but no power to pin 17, spot is empty on the 35 pin connector.
Wire Color ID
B = Black
Br = Brown
W = White
CH = Dark Brown
R = Red
Y = Yellow
G = Green
GY or Gr = Grey
LG = Light Green
P = Pink
DG = Dark Green
V = Violet
L = Blue
PU = Purple
SB = Sky Blue
O or OR = Orange

The wire that i colored yellow in the pictures is actually Brown. The wire in the pictures that I colored blue is actually Green






Rectangle Slope Schematic Font Parallel
Rectangle Schematic Font Parallel Engineering
 

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The differance between the the 1980 and the 1983 is the "dropping Resistor" used on the 1980. Dont mix the ECU's, the 83 does not work with the 80 harness. The 80 ECU will work with the 83 harness if you add the dropping resistor. You can use either wire harness/ECU combl, it won't matter. When Datsun placed a wire in the 35 pin ECU connector it stayed in the exact same place form 79-83. The power comes in behind the plastic panel on the passenger side fender behind the battery, thats where the fuseable links are also.

I run a 1981 ECU in my 1983. Read about it here
1983 280 z 2+2 ECU

If you have any questions feed free to email-test-call me
[email protected]
seven-zero-one 471-fifteen,thirtyfour
Craig (AKA Kickstand80)
 

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Behind this panel (blue outline) is the EFI relay and the interconnect with the fuseable links. The links are under the cover right next to this panel.
Vehicle Car Hood Motor vehicle Automotive design
 

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EZ thing to do is get a 1980 ECU. Ebay. Replace the ignition control module on the distributor with a early (single plug E12-80)version. Extend the coolant temp sensor wire to reach the back of the head where the cylinder head temp sensor is located (plug and play)

You will have to strip some tape off each sensor connector wire to identify the wire color to figure out where each goes. Get them correct. 4 of the connectors are identical.
 

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Discussion Starter · #13 ·
Hey kickstand thank you so much for the info!!! So i actually have the engine,harness,ecu, and all sensors from an 83 so in reality I'm just hooking everything up as its own unit in the 80 body.

So i will state my progress, sorry for the jumbled pin info below

I found the ecu fuseable link in that box you mentioned, hooked it up and i currently have a good ground at 15, currently pin 2,5,7,8,17 have power with just the battery connected. When i turn the key the only pin that turns on is 18. There is definitely something wrong here lol, i took the ecu apart and it looks emasculate on the inside so I'm pretty confident with it working( obv right now harness wiring isn't right so i have not seen the ecu come on)

Issue 2 i am having.

When the key is turned i get power from the single wire connector that goes into the brick, weirdly i am getting no power from pin 26 on the brick even though the wire that i think goes to 26 (key ignition) has power. Very confused lmfao please help.
 
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