'92 vx fuel pump fails after short trips.
 

So this just started happening in the last month or so. I would take a short trip, shut off the engine, be gone a few minutes and come back. When I start my car, it would instantly die/stall. After a few days of this, I realized I did not hear my fuel pump prime the line when I turned the key to the "ON" position. If I just let it be for a minute or two after it stalls, it's fine. Or if I just keep turning the key to "ON" every so often to listen for the pump, it will be fine. It has never (yet) stalled while running, only just as it's starting up, and only after a short trip when the engine is heated up. It's never (yet) happened when the engine is cold. And it doesn't happen every time I take short trips, only about 1/3 of the time.

My first idea was whatever system/sensor is sending the signal to the pump when starting is where the error is. What would that be? The ECM? I was told the ECM was "bad" when I got the car (although all my tests showed it to be good), but that was years ago and this *just* started happening.

I haven't done any work on the car since last September. (Replaced the dizzy)

Any ideas? Thanks in advance.

main relay is bad.