'79rx7

I put the 86 engine, harness, and cpu in my 79 but i can't get the ignition to work, does the cpu get it's power from the coils, or from the engine harness??? I have a 87 workshop manual that shows a wire that leads from the battery to the cpu it goes through numerous plugs and changes colors quite a few times but it ends up at the cpu, or so i beleive. If i'm right it looks like i can tie into it with one of the plugs from the engine harness that a by the cpu, with a fused 7.5 amp fused line from the battery, does this sound right??? PLEASE HELP

Racer X

Sounds like your on the right path.Are your coils getting 12v?what are you using for a pump now?

j9fd3s

yah, it goes to the engine harness under the dash i think



mike

'79rx7

ya, the coils are getting 12V from the main relay, and i'm using a walbro 255 inline pump

Racer X

Cool.Good luck I think mike is right about that power wire.Let us know how it goes.Best of luck making the SA a EFI car.

'79rx7

Thanks at this point in time i need more than luck! I'm going to try that hopefully it warms up a bit, i can't stand working with numb fingers. I'll let you know how it goes.

'79rx7

well i tried to run the hot wire from the battery to the cpu, but it still doesn't work, the coils have 12V but no spark, i'm going to borrow a friends 86 and test each wire that plugs into the cpu with the ignition on to which ones get 12V then if i find any that do where mine doesn't just run one! I hope this works...



asuming i undo the fuses of the ones that i already know where mine has 12V then just look for one that does, maybe i missed something?



I'll be sure to let you know what i find, also i tried another cpu (not the problem)

Apex13B

did you say that you are using a 79 CPU?....or was that a mistake

'79rx7

no 86 engine, harnesses, cpu; in a 79 body

j9fd3s

the ignition system on an fc is simple. the cas sends its signal to the ecu, and the ecu sends its signal to the coils, so it can basically only be those 3 things or the wiring in between



mike