Just finished rebuilding my 4d55 pickup (don't get me started on the difficulty finding parts <img src="/forums/images/graemlins/scared.gif" alt="" />) and am having difficulty with starting. I had it running (after some starting fluid) but it would run for about 30 seconds then stall out, as if it had run out of fuel, not just suddenly die. I could restart it almost immediately, but would do it again. I drove it up the street and it died several times in just a couple of blocks. Sure sounds like a fuel issue. Would adding an electric fuel pump to presurize the line help at all? I'm worried about perhaps sucking air from somewhere just using the injector pump to suck the fuel from the tank.