I have a non start issue. It's a '90 5.7 with HSR. I have spark and good injectors. With key "on" I have no fuel pressure on the gauge but I can "hear" the relay clicking, also I "think" I can hear "some" noise in the tank. However, when I bridge (orange and grey wires) the relay plug I can see some pressure slowly building up in the gauge and a weird noise in the tank like a vibration. The vibration stays as long as the wires at "bridged". The pressure stays at around 30. Could it be bad relay, bad pump, or both? Thanks.

 

A relay is a much cheaper start. If you jump the relay and the pump runs, start there.

 

It sounds like the pump is running but rough. Another way to test is if your ALDL has a G terminal (facing the ALDL, far lower left terminal) apply 12V there, that's about the same as jumping the relay.

 

I like to test voltage at the connector under the rear of the car with a multi meter when things at the relay are testing good. That's the second to last leg to the pump (the last leg is the connector on the top of the sending assembly - mine had a wiring fault there)

Make sure you're getting your voltage to the connector there, then you can use a 12v source to prime the pump direct too just to be sure.