Truck isn't starting...

Codes are all good.

I know it's not (at least it shouldn't be) the starter, battery, fuel filter, air filter, fuel pump, MAF, IAC, flywheel, rotor cap, sparkplugs.

It will turn over if i spray starter fluid in the air-intake and run for a couple secs, but then dies.

Makes me believe its the computer, or a leak in the line somewhere.

Any suggestions before i take it to a mechanic?

Thanks

*EDIT

Couple other notes..

When i was able to drive it last. i notice when i tried accelerating (pushing down the gas pedal) it seemed like it suffocated the engine and gave me a couple chugs when i did. luckly i was able to make it home the last mile. truck didn't start the next day. I changed out the fuel pump cause i wasn't able to hear it prime and thought that was the cause. but it still didn't work. there were only 2 codes that came up before i changed the pump. they were the "Air temperature sensor" and "radiator temperature sensor" but after i changed the fuel pump they went away.

 

The fuel pump gets its power via fuel pump fuse or fusible link, only the fuel pump is on this power circuit.

There is a fuel pump relay that needs to close to pass this "fused" power to the fuel pump.
'92 might have this relay located UNDER the power distribution box in the engine bay.
There are 3 relays, Green base is Fuel Pump Relay, Brown base is EEC Relay(EEC relay powers computer, Fuel injectors, and fuel pump relay(not fuel pump just the relay)
When you turn on the key the fuel pump relay gets power(EEC Relay), but has no Ground so doesn't close.
The computer Grounds the relay to close it, it should do this for 2 seconds when key is first turned on and then Ground it again for as long as the engine is above 500rpms(running).

On the pre-'95 Rangers, OBD I, there is a test port in the engine bay, usually on the drivers side by the firewall.
On this port is a slot to by pass computer control of the fuel pump.

Diagram of this test port here: Ford Ranger - Testing EEC-IV Equipped Engines

Look at the diagram, it shows the Fuel Pump Slot, if key is on, and you Ground this slot the fuel pump relay should close and fuel pump should start if Fuse is good.
This slot is connected to the same Ground wire the computer is for fuel pump relay control.
So if you take a wire and put it in this slot and then Ground the other end of the wire you should hear the fuel pump relay "click" and the fuel pump should come on.

If you hear the "click" but no pump then check it's fuse, 30amp in Power Box.
There is also an inertia switch in the passenger footwell, below glove box or in upper kick panel, this switch cuts power to fuel pump if there is a sudden stop or roll over, i.e. accident, it has a reset button on the top, these can fail, but it isn't common.
The fuel pump motors Ground is often hear the inertia switch, it will be a black wire often with an Orange wire(fuel gauge ground) on the same ground point, no ground for the motor is same as no power.

If you don't get a "click" from fuel pump relay then it is either broken or relay has no power.
Black base relay can be swapped with Green Base relay, for testing.
Black base is WOT(wide open throttle) relay, it shuts off A/C when extra engine power is needed.

IF you hear the "click" and fuel pump starts, then yes computer is not Grounding the fuel pump relay, this could just be a bad wire.
Pin 22 on the computer is the fuel pump relay Ground control.
Diagram here: ford eec iv
The computer has several Ground wires, they are not shared internally, so it could be a bad ground wire for the computer.