Finally went to install my megasquirt and start the car...
 

to find out I've just wasted over a year of my life! HOOOOOORAYYY!!!!!!


I purchased the harness that plugs into the PCM, runs along the passenger floor and plugs into the cars harness from someone online. Received it. Traced out and tagged EVERY wire on the harness. Removed the pins of wires I needed, clipped the ends off, stripped, installed into MS relay board. Made my relay board harness, wired it all up. Wired in a new power and key switched wires, grounds, everything was so perfect. MS is ready to hook up and run the car.


Spend 3 hours trying to unplug that harness from the cars harness, to find when I finally got 2 of the three plugs removed from the car.. they're NOT THE SAME AS WHAT I HAD!!!!!!!

:eek:

PCM connectors IDENTICAL. Wiring color code IDENTICAL.

Harness was supposedly from a 1994 OBD-I miata. I have a 1995 OBD-I miata. I hate my life.

http://www.jugrnot.com/CRW_9154.jpg
http://www.jugrnot.com/CRW_9155.jpg

FUCK!

im confused to what the original connectors look like, and what your new ones look like compared on each side...looks like the ECU side is good but the other side isnt?

Yep! Since it only took an HOUR to get my hand up in there to unhook that jumper harness, I couldn't really compare the two harnesses before I started.. only checked the PCM side which was the same!

Second picture the TOP most white and blue are the cars OEM jumper, and the bottom left white and blue are my jumper I modified. This sucks. All isn't lost, but I really did waste a LOT of time on that making sure Everything was perfect.

I/ve never in my life seen the connectors in the bottom picture.

i think those are the connectors up along the firewall. there is a short patch harness that runs from the ECU behind the seat...along the door through those white plastic channels...up around the heater blower to the main wiring harness.

I just wanted to bitch, I came up with a solution to make this an even better project.

Ditching that piece of shit harness I wasted so much time on. At least I learned a lot about the pins in the factory harness, and can now utilize what I've learned to apply it to another project in the future.

Brain posted part numbers in the "how to DIY" Thread to build a boomslang style harness, which I've ordered the 64 pin part of, and will just solder on wires for that to run into my relay board. Problem solved, and that god damn connector costs like six dollars, I paid 70 for that farking jumper harness.

You should take some pictures of what you built as a whole. I'm having trouble visualizing what you built that is unlike what everyone else on here has been building and using. There is only one harness that needs to be made, what makes your car any different is what has me curious as to what you built.

it's the connector from the firewall back to the ECU behind the rear seat.

But why do it that way? Did he want the MS to be in his glove box?

No, I took the jumper harness that runs along the passenger floorboard to behind the HVAC blower motor and removed the wires I needed to install them in the relay board. I bought that harness in like 2005 and was really difficult when I bought it to find a diagram for it, finally found one, planned everything out, removed what I needed, checked everything like 11tybillion times then found out I'm screwed.

Was planning on leaving the meagsquirt and relay box behind the passenger seat. Anymore now its pretty much a non-issue, but I'm still upset I wasted time and money on that harness but at least now I know what I'm looking at getting into to complete it. Just wish it worked out cause I'm really excited to get this thing rolling!

I selected this method because at the time I only had one car, the miata.. So this would allow me to plug in megasquirt and play, learn, etc while maintaining reliable transportation. Now thats not an issue either with three cars and a work vehicle I don't ever drive my personal cars anymore. :)

Some switches on the stock ecu case would have done the same thing dude. I am sorry for your loss of time/