ok so i am thinking about going with a megasquirt setup and controlling both spark and fuel and fuel pump and such,

my question is can i basically get rid of the whole wiring harness. i noticed that there are also a number of wires that branch off from the harness by the passenger side kick panel and head toward the back of the car. does anyone know where they go exactly or what they do?

if i do this setup i would like to get rid of as much of the original harness as i can and just start from scratch. ( i am planning on using the megasquirt relay box to help out with some of the stuff in the engine bay)
thanks,
-dan

 

OK this may not be too helpful as I am very new to the ms, but from what I see you almost have to get it running on the bare basics. Here is a diagram I found on here but the harness I am using is identical with the exception of the O2 sensor.

 

Yeah, my plug 'n play setups only use a fraction of the pins on the stock plug.

You'll need what's in the diagram that BklynRX7 posted, plus 7-8 other wires (4 for the CAS signal, and 3 for the spark outputs, 1 for the fuel pressure regulator solenoid, if you feel like using it)

Ken

 

When I built my wiring harness I found the following wires that connect to the plugs in the passenger kick panel:

+12v from main relay, for injectors
Cruise control motor
Windshield wiper
IGN switch
+12v constant
+12v from ign switch
Cooling fan switch

There's some other wires that run on those plugs, but I did not take note what they go to, you can take a look at the FSM and see what else those plugs connect to.

 

ok so you basically can just start from sratch. have any of you ever used the relay box, and if so how much did it help instalation. its sounded like it might make the process a lot easier. im mostly just concerned about pulling the harness and then having a lot of other crap stop working because they were connected. does any one have more info about what the harness wires run to, (ive already found diagrams for the three ecu plugs, im just worried about the others over there in that area around the ecu
Thank you
Dan

 

I started from scratch. Photos of my harness build:

http://pictures.nsfabrication.com/ma...g2_itemId=6028

I, personally, would not recommend the relay box. Our cars already have all the relays we need to power everything in the vehicle. In my pictures, there's a new main relay next to my MS, which supplies power to the MS, ZT-2, and injectors. The stock main relay still supplies power to the coils. You can still use the stock relays for power, I chose to use a new one because I pulled a dedicated "hot" wire off the battery for the MS.

The relay box is more or less aimed towards cars that don't have power relays, which would be something thats being converted into EFI from carb. It's not really necessary on a car that's already injected.

 

gross polluter- thanks for the pics, that helped a lot. what is the plug in pic DSCF2727 is this an ecu plug or is this one of the harness plugs that runs toward the back of the car? It looks like you have a great setup, i wish that was already on my car lol. oh well maybe someday soon.

so correct me if i am wrong but you are saying that you can just reuse most of the stock power wires and then run the rest through MS. were the stock power wires run through the stock ecu or do they come straight from there corresponding relay.
thank you
dan