'91 ecu troubles

[greenfield54]

Sorry mine is actually a 96 with no oxygen sensor installed. Reason is that during that time all gas sold here still use lead. This unit came fully assembled from the factory. The heavy thermal insulation and heating system are still there. These I removed after gutting the car in 2013 when we bought it. It is OBD2 but I found the check engine light disabled as indicated in the schematic. A blind which is confirmed original from the factory was used to cover the light with no bulb installed. When it was still running fine we used a scan tool for my nephews 2012 Hyundai but registered no fault codes even if I intensionally pulled the coolant temp. sensor. The Haynes manual is fine but is not what most would expect from a service manual being for U.S. units with all the bells and whistles. And U.S. units don't use Siemens ecu so I was in limbo when finally a friend emailed me a schematic for a MAP based Siemens ecu. I suspect that fault logging software was omitted during the programming. I have experience programming industrial Programmable Logic Controllers (PLC) and we can omit fault monitoring/logging if the system does not really need it. The first time I went under the hood it started (roughly) but died almost instantly. There was an intermittent weak spark from the plugs so I proceeded to do a bench test of the dual coils which produced no spark. It drew very heavy current so I concluded that the primary windings shorted out. A new original coil made no difference. I monitored the signal that triggered the coils with a light bulb. At first it flashed dimly but now no more signal. The ecu still cycles the fuel pump after switching on the ignition and flashes the check engine light so this means that the microprocessor chip is still alive. The injectors also cycles when starting but the engine fails to start due to no spark. A friend replaced two electrolytics which appeared bloated but left the 100 mfd alone including the tantalums so I wonder, can this be the problem? The ecu was embedded in one inch thick potting compound which took me more that a week to peel off. I hope this helps give a clearer picture of what I'm against. We are already contemplating to part out this car. Thanks. The engine is a Beta 1 G4GR of Mitsubishi design.

Regarding the timing belt and cam, everything is in order. I changed both the cam and crank position sensors with original ones (very expensive). I checked for 5vdc and continuity of the wiring harness. Checked all grounding (sensor,logic,B-). All signals to the ecu (B+,Ign,Trans in park signal,etc.) are present. I have not pulled the valve cover though to see if the cam is actually turning. I only removed the belt covers to check.