So I "inherited" an LTX-8 with the FC that I bought last fall. Only it has yet to be installed and the harness has been FUBAR.

So my tough question is: why do the wire colors on my ECU harness not match those on microtechs wiring diagram? (I'll prolly buy a new harness, but I'm thinking it may have to do with the harness being for a different application)

And my easy question is: what mounting location should I use for the ECU? The stock location seems obvious, but since these things are made for racing applications I had heard that they generate a significant amount of heat and it may be better for me to mount in in the engine bay.

any thoughts are appreciated! thanks!

 

I usually put them in the glove box so that they are easy to unplug if you have to and easy to put a hand set on.

If none of the colours in the diagram are matching up with your wiring loom, good chance some dodgy **** made his own.

Show us the harness?

 

+++1 for the glove box works every time !

 

Ok, so a month after I ordered a new harness from A-Spec (which I do not recommend since these guys were uncooperative in refunding my money) I decided it was taking absurdly long, so I made my own.

It came out great, but I'm having a little trouble interpreting the wiring diagram. Mainly it is the part on both pages of the diagram where the pink wire from the ignition is depicted.

Does this representation mean that I am to splice into a switched 12v wire from the ignition switch on both pages? or does it mean that the pink wire is supposed to be switched at the ignition and go from the EMS to the ignition coils? it would be great if someone could clarify this for me. (I mean if it is meant to be switched wouldn't it work if I wired in a separate kill switch?)

Thanks for all your help guys!

 

your talking about the pink wire thats running to the tan on the leading coil?

 

Ok

You need to give the microtech a SWITCHED 12v.
This is very important otherwise the ecu itself dosnt switch on.

For the coils. Run their own switched 12v signal. (and if you dont have a good one, use a relay and use the switched 12v wire going to the microtech to trigger the relay)

And this is normally the pink wire on a normal microtech harness.

ALso with your harness. You should have let me know. Could have had one shipped out to you straight away.

 

So it should be spliced to look something like this?

Microtech EMS_______________(switched 12v)
Ignition Coils________|

Or do I not want to have the 12v signal coming from the same source? Either way this helps quite a bit guys, thanks a lot.

 

It can come from the same source as long as its a good source.

 

D'oh! Just when I thought I had it all sorted out, I ran into difficulty while wiring in the fuel pump. All the microtech diagram shows is a wire from the relay to the pump and then one to ground on the frame. I've got 4 wires coming from the pump unit, with the key on top:

Black |Red
Black/White|Blue

sadly the factory wiring diagram goes:

Blue/Green|Black
White/Red |White/Green

This is after you translate the color codes. The dodgy rat-bastard who owned this car before me appears to have tinkered with it, so should I just ignore the wire colors, pray that I get it right, and figure out later how to wire in the fuel gauge? or do any of you have an idea how I can make sense of this ****?

 

Go to the boot.
Uncover the fuel assembly.
And trace the wire down to the pump.

On aus spec fcs it is a thick black/white wire that goes down to the pump at the fuel assembly.

Do not dodgy it up and tap in at the front. run a new 6.5mm wire to the back.

the fuel guage is completely irrelevant of the fuel pump and you should need to play with this at all.

 

hey how much do you charge for a microtec harness for a s4 t2?