engine wont stay running,dies after a few seconds past cranking on 1993 GMC Vandura 2500

when I cycle the key a few times, seems to build up fuel pressure fine. when I start the engine it runs a few seconds then dies out. I can see the fuel spray lessen at the TBI injectors to the point of just a few drops. I can do this over and over, same result. Seems that fuelpump must be working. I dont have FP gauge, Relay doesnt feel to click "off" by itself, put in a new fuelfilter.Can ECM cause this? This is van conversion, can't find the ECM, ideas?

Asked by for the 1993 GMC Vandura 2500
1 answer
may not have enough pressure. get it checked by a shop to confirm.