I just bought a 1987 Nissan Pathfinder with the z24i motor. It sat in a guys yard for a few years...I drained the fuel, replaced the plugs, coil wires, intake side coil, plug wires, fuel drained and refilled, new fuel filter, intake gasket, bypassed the EGR, and I am not getting any spark from the intake coil...the one with the four pronged ignition module. So it runs good at low power, but after applying about 50% throttle or more the engine dies until the RPMs drop. THe ECU is cutting out the exhaust spark (I think normal) under load and that leaves me with no spark.

1. I am getting code 21 from the ECU
2. I replaced the coil...no improvement, swapped coils, no change.
3. I don't know if the ignition module is the problem..cant swap them as one is three pronged and the other is four.
4. I looked at the wiring diagram and varified 12v and ground to the ignition module...but the other two wires go to the the ECU I believe and that is a mystery to me.
5 The scematic shows four wires coming from the crank angle sensor, wondering if the signal from the CAS is shared for the two coils or could that be the issue. Is that even a possibility...I thought maybe if the exhaust side works, wouldnt that mean the distributor is signalling the ECU properly.

Right now I think its either the distributor crank angle sensor, the ECU or the ignition module.

Am i on the right track? Anyone in the Tampa area have the no how to help me narrow this down...I've bought enough parts (would have anyway) and really just want to diagnose this properly...?
Sincerely,
RC