When you turned the key on, did you hear the fuel pump come on for 2 seconds?
It is not quiet you can usually hear it in the cab, a "hum" and then a "click" when the fuel pump relay opens and pump shuts off.
If you don't hear it come on each time the key is turned on then it could be the fuel pump relay is not closing as it should.
Not sure on the 1992, but fuel pump relay should be in or under the engine compartment fuse box.
Have a look here for under: How To: Change A Fuel Pump Relay-91-94X - Ford Explorer and Ranger Forums "Serious Explorations"®
Green base is FP relay, Brown base is EEC relay, Black base is WOT(wide open throttle) relay, you can swap FP relay and WOT relay they are the same.
WOT relay is only used to turn off AC when throttle is wide open and you need extra power
But FIRST..........there is another test, in the engine compartment usually on drivers side near firewall is the OBDI test port.
Have a look here for what it looks like: Ford Ranger - Testing EEC-IV Equipped Engines
It is usually just loose hanging near power brake booster, gray or black plastic
In the second drawing down you will see the "Fuel Pump" slot IDed
That slot's wire is connected to the computer wire and Fuel Pump Relay wire, that wire used to turn on the fuel pump relay(close it), this is done by Grounding the fuel pump relay.
If the key is ON and you use a Grounded jumper wire in that slot you should hear the FP relay "click" and then the "hum" of the fuel pump.
If you hear the click and hum leave jumper wire connected and try to start engine.
It could be fuel pressure regulator is not closing and system can not build up enough pressure in the 2 seconds the fuel pump comes on, even if you Prime it multiple times, only when you get engine to start, with brake cleaner and above 500 RPMs, does the fuel pump come on full time and system has enough pressure to continue to run.
But same could be said for fuel pump check valve.
You could try loosening the FPR's return fuel line, put a towel under it, then turn on fuel pump and see if alot of fuel flows out of it, if so then it would most likely be the problem.
It should be closed tight with no vacuum pulling it open.