Only runs with fuel pump relay out.

So my buddy did an engine swap in his running cherokee. Got it back together and it wouldn't run, had no spark. Well today we got spark, but it was bad spark, so we tested coil and it was good, so we swapped in a new distributor, and it got better, not perfect but good enough for now. So it still won't start. I decide to see if injectors are firing by turning key so fuel pump builds pressure, then removing fuel pump relay and cranking the engine over. Well, much to my surprise, it fires up and runs till it runs out of gas. Put in relay, won't start. It will only run when you pull the fuel pump relay. Has anyone ever had any sort of problem with this? Ballast resistor is bypassed and always has been. Christian