i have wired the efi pinto this week and have a problem.
When the key is turned and the engine is cranking i dont get any spark at the leads but just as i let go of the key to stop cranking the engine i get a spark.What is the problem can anyone help?

Have you connected the ecu/coil feed to the acc position(yellow wire) on the key switch ?

No i have nothing connected to the yellow wire all the wires have been connected at the ignition switch as per the build manual instructions.

Is there any other function you can test that the ECU is getting the correct signal to trigger the coil pack, is there a rev-counter for example that would be fed from the same signal.

The ECU probably grounds its outputs to dischage them when its is shut off, hence why it gets a spark when you've finished cranking.

Could be a faulty ignition switch not putting out any power to the ignition circuit when cranking. Easy to test with a multimeter.

ignition switch is working and power gets to the coil. i can ground the coil to produce a spark but it will not spark when the engine is cranked. i have tried with two other dizzy's and tfi amp packs but had no joy.

Hopfully, here is alink to the wiring diagram that i used to get my pinto to run.

I had the same problem, it would fire, then stop when you released the ignition.

Linky

As far as I can see from the manual, the ignition module needs two +ve feeds:

Black/green - from the cranking feed - joined to Blue/black on the ignition switch

Black - switched ignition feed - joined to black yellow on the ignition switch.

So the black/green will get +12V when you are operating the starter

and the black will get + 12V both when operating starter and when running.

I don't know why it needs two feeds - maybe it was designed for a system (apparently not used on the Sierra)where all the ignition controlled feeds are cut while cranking to give max power to the starter:

maybe the presence of +12V on both wires tells ignition amplifier to retard the spark or speed up the decay to give a stronger spark when cranking.

In any case, you need +12V on the black wire when it is running.

I'm going to connect it as per Sierra manual
HTH

i think i have sorted it. i found a break in the signal wire between amp pack and dizzy.
Fingers crossed that i fire it up tonight.
Thanks for all the suggestions.