AE86 4A-GE 16v engine harness rebuild

[FanIsHere]

Hello,

I was curious to know if it's possible to make a 4AG-GE bluetop 16v engine harness for the AE86 from 0 by having a spare OEM engine harness.

Mine seems to have some leaks, so I don't know how to repair it.

[Bean]

It's a lot of work/time consuming but yes, ideally you would try to source new pins/shoes? for the connectors but you can work around that.

Personally I would check all the wires on the harness you have first and only replace the ones that are needed. Take a lot of pictures and label everything before you unwrap it.

[Project D]

Of course you can build ANY harness from scratch.

I actually find it WAY easier to start from zero than trying to modify an original harness.
(Mind you, that's my own opinion and it heavily depend on your skill and how familiar you are with that kind of task)

The last one I have done: (my friend's 4AG swapped TA60)

[Nakilad]

(01-16-2020 09:02 PM)Project D Wrote:  Of course you can build ANY harness from scratch.

I actually find it WAY easier to start from zero than trying to modify an original harness.
(Mind you, that's my own opinion and it heavily depend on your skill and how familiar you are with that kind of task)

The last one I have done: (my friend's 4AG swapped TA60)

That looks great! Very tidy, good job!

[FanIsHere]

(01-16-2020 08:17 PM)Bean Wrote:  Personally I would check all the wires on the harness you have first and only replace the ones that are needed. Take a lot of pictures and label everything before you unwrap it.

How can I check all the wires if they are not plugged and the motor isn't running? If I have a leak or something, I wouldn't notice.

(01-16-2020 09:02 PM)Project D Wrote:  Of course you can build ANY harness from scratch.

I actually find it WAY easier to start from zero than trying to modify an original harness.
(Mind you, that's my own opinion and it heavily depend on your skill and how familiar you are with that kind of task)

The last one I have done: (my friend's 4AG swapped TA60)

It seems a pretty good job actually! Where did you sort all the plugs and connectors?

I'm not familiar at all, but I would like to give it a try. I have nothing to lose, except time and some money.

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The other way to go is to go deep in the wallet: standalone ECU.

But I have to wait for another year to collect the proper money for a good aftermarket ECU and program it.

[Project D]

(01-17-2020 06:22 PM)FanIsHere Wrote:  How can I check all the wires if they are not plugged and the motor isn't running? If I have a leak or something, I wouldn't notice.

You could check the resistance and continuity with a multimeter.
But honestly unwrapping / cleaning the OE harness take a lot of time and is very messy...
If budget is a huge constrain, fixing what is wrong with it is probably the best way, but god I'd do anything to avoid messing with that !

(01-17-2020 06:22 PM)FanIsHere Wrote:  It seems a pretty good job actually! Where did you sort all the plugs and connectors?

I got all the OEM connectors from Ballenger:
https://www.bmotorsports.com/shop/index....th/109_484

The other option is china (it's incredible what you can find there )

In my case I also use a combinaison of motorsport and military connectors, wires and heat shrink (Deutsch DTM, MIL-C-38999, M22759/32 and DR-25)
But that's not for everybody.

(01-17-2020 06:22 PM)FanIsHere Wrote:  I'm not familiar at all, but I would like to give it a try. I have nothing to lose, except time and some money.

Be careful, money goes fast with this kind of stuff. (Trust me I know...)
You have to consider the hardware (wires, connectors, etc...) but also the tooling.

At a bare minimum I would recommend the Hozan P-706 crimper.
I's a must for Japanese connectors.

(01-17-2020 06:22 PM)FanIsHere Wrote:  The other way to go is to go deep in the wallet: standalone ECU.

But I have to wait for another year to collect the proper money for a good aftermarket ECU and program it.

MS clone like EFIgnition 46 are not super expensive.

The ECUmaster EMU Classic is also a pretty good value for the money considering it has a internal wideband controller.

If you are not using the OEM ECU I would highly recommend to modernize the wiring (sequential ignition and injection is a must)
On my friend's carina I have used a set of 1ZZ coil and Sard 300cc injectors combined with a MS (heavily modded DIYPNP)

[Power_uP]

This may be a stupid question, but what is a harness leak? The only type of leaking harness I've encountered until now is when a small oil leak causes oil to run up the wires and into an ECU. If so, then in most cases I wouldn't think a new harness would be entirely necessary.

[Project D]

https://en.wikipedia.org/wiki/Leakage_(electronics)