'90 beretta 3.1 cranks over but won't start.

I have a 1990 beretta thats cranks over good but will not start. About a week ago I was driving and it just shut down like someone turned the key off. It did not sputter or nothing, just died. I looked at all fuses in fuse box and they are ok. I checked for fuel, and I have plenty of pressure. The battery is good and no wires apart on the ignition switch. I pulled a plug and checked for spark but I didn't see any. So I think I know where my problem lies but how do I zero in on the actual cause. I had a secound ECM from the previous owner when they said they had it replace because of lagging problems. So I figured if the problem was the ECM, this other one would be good enough to at least start it. So I swap the PROM chip and put it in, still nothing. Could this be a problem with the Ignition control module (under the coils)? Or could there be a fusible link or relay or something? Can someone test the ECM or the ICM? Any help is appreciated. Thanks.

Ok I replaced the ICM and the Crank sensor. Still won't fire up. One of my neighbors told me they knew of someone who had the same problem with a simliar engine and they said it ended up being the oil pressure sensor. Could a bad oil pressure sensor cause an engine to die and not fire back up?

Get a Haynes manual follow the instructions for checking the module. Advance and Auto Zone will check them free if you take them to the store.