Am no expert on this but how this works is the two plug on the distributor is for base timing as the engine turns and reaches about 400rpms the engine starts then the 4pins side of the module takes over and sends a signal to the computer to control the timing of the engine. They call this the est side if there is a problem on the distributor module or the wiring going to the computer it will not stay running check the 4pin wiring and the module if it all checks out it is possible you have a ecm problem.