FIRST and foremost, check the fuses for continuity even if thery look good, then try jumping out the FP relay as suggested by another writer.
I believe we're talking about the same part, and failure is not quite so uncommon, but more not the first thing that comes to mind. I replaced the module in my 87 740 Turbo last month after a week of stalling in traffic then either immediate restarts or 3 minute delays to start. Lift gently on the harness as it enters the module and have a helper crank the engine (Do not worry about shock as there is no more than 12vdc at this module.). The car may well start. Then try a light (!) tap on the module while your helper is cranking the engine. The light shock may make the loose connection internally. The Hall sensor in the distributor is less likely to fail than the ignition module.
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If at first you don't suceed....it's time to sell it! ;)