1JZ harness extension question?

[SuperNova]

I've been collecting parts for the swap for a couple of months now and I'm about to start extending my harness the 18 inches it needs to fit. What I'm not sure about is the sheilded wires. Can anyone tell me which wires they are, or what they go to and how many? I've read that they need to be completely re-wired from ECU to sensor. Is this true? I'm trying to make sure i know exactly what I need to do before I start it.

Also, is there anything else I should know?

(It's a Soarer 1JZ going into an 87 NA by the way if that helps any.)

Thanks.

 

[Evilempire1.3JZ-GTE]

Your alternative is simple.
Dont extend the harness enlarge the speedo hole then run the harness to the glove box through a slightly larger speedo hole.

The only wiring work is to splice 2 wires at the junction box by the battery for your alternator. I am sure you also know you need to run your thick alternator wires to the JB also.

Then simply build a small jumper harness that goes in between your MA70 body connectors to mate to the 1JZGTE EFI harness. Then figure out work is which oil system to use? 3 options here

1 Use the factory 1JZGTE oil level monitor & computer most people shrug this off and dont add it and the ecu with light to thier car. Just use the old fashion check oil like normal people routine.

2 Use the factory 1JZGTE idiot light pressure switch it will only go off after the fact the engine damage is done and its to late.

3 Use the 7MGE oil pressure gauge.

You could use all 3 systems
but if you decide to use 2 & 3 you have to add a wire to go from the pressure sensor to the gauge.
This is simple to do use the 2JZGTE or 2JZGE I forgot which one but it haves a 10mm tap in the midddle of the union bolt for the oil cooler. Screw your oilpressure sensor into that you have to trim the cooler a little bit but it will screw in and secure.


The last thing to decide is if you want hydrofan setup or 2JZGTE waterpump cooling system.
otherwise you have to add the hydrofan ECU & wiring such as the JZA70 radiator with the water temp sensor threaded into the lower left corner.

I would personaly opt for upgrading the cooling system to the 2JZGTE setup then switch over to clutch fan or Efan setup. Easier to find parts this route also.

By the way if you extend the harness you need to do shield jumper splices if you dont do this right you get alot of noise in the important signals that goto the ECU & risk kaboom!

I would not ruin a perfect harness you have no idea what a virgin harness is worth because of someone elses wiring nightmare.