did you measure the power to the solenoid. ? when it shuts down, are there engine lights on the dash. when it goes down. if shaking will not restore the power but with the engine running and you shake it will kill the engine, YOUR trying to duplicate the issue at this point) than pinpoint and fix. this is why i said to shake, and what you just described to me is that either there is a power interruption to the ecm for that split second or there is an internal failure within the ecm, as i asked was a test ecm put on the engine to eliminate that possibility ?
Your welcome. Thanks again