well i havnt really posted any of my swap on here because honestly, who wants to see another 13b swap into first gen ? :P

I have completed all the drivetrain swap, but im having problems with the ecu. The car is an 85 GS. The motor is an s4 NA 6port, rebuilt. NA s4 tranny with no mods, And i took off all emissions, AC, power steering, and all dash wiring.

The problem is i am trying to run both the s4 ecu and the 12a ecu at the same time, one for motor swap stuff, and first gen ecu for everything else. I cannot figure out how to power and correctly wire the s4 ecu to get it to work. I have no spark, no fuel, no voltage reading on anything except the 12v wire i have going to the "battery" pin on the ecu. HELP!

 

the stock 12a ecu is just for emission controls for the 12a,it's useless for the new engine.

 

I believe the stock 12a ecu is needed for the fuel cut relay(under the dash on the steering column). I know you can jump the relay if it's broken, not sure if the jump will work without the ecu. I guess you can wire the fuel pump to on with the ignition, or with a switch(not as safe as with the relay).

 

Just realized you must be running a efi fuel pump.
Hooked up the the stock wiring?

 

well i havnt got to the fuel part yet... first snag was here at the ecu. For right now the 12a fuel system is still in tact. I have the 13b second gen stuff still available for taking. As far as the wiring for it, i have the fuel pump cut relay wiring still connected to the 12a ecu. as far as the actual relay connected, im not sure, what does it look like?

 

Its on the right side of the column.

 

so thats near the steering column? yea i have that connected. I found one problem where i had the coils double grounded... Apparantly black w/ yellow stripe is different on the two harnesses. On the coils it means 12v and the battery its the ground. WTF! hah..

So now im at the point of wiring the main relay. I didnt wire it up and i guess i need it.... also need to find where to put the yellow/blue wire from the trailing coil on the tachometer. Other than that, the coils will be wired up.

Can someone show me how to wire up the main relay correctly?