I have a 97 jimmy 4.3. Was driving to work and it died, wouldn't start again. I was on the 2nd fuel pump already. So, here's where I am: put in new fuel pump, new filter, new pressure regulator. Tested injectors, all OHM to spec. It will start on starting fluid. Has 60 PSI at the fuel peckcock. Have a relay on order. Is there anything other than the ECM it could be???? I'm stumped.