Can any one tell me if the computer controls the fuel pump and what it does if so?

 

Yes, the computer controls the Fuel Pump Relay in the engine fuse box.

It controls the Relay's GROUND wire

When you turn on the key the computer will Ground the relay for 2 seconds, and 2 seconds only.
But it will do this EACH TIME you turn the key from off to on

Computer will Ground the relay full time once engine RPMs are above 400, engine is started

The relay passes 12v from the Fuel Pump Fuse to the inertia switch in the cab and then to the fuel pump

Battery----fuse-----relay---------------inertia switch------------------------fuel pump---ground

For 1993 computer the Ground control wire is pin 22 on the computer connector

You can "hot wire" the relays ground using the OBD1 connector found in the engine bay

Look here: http://www.therangerstation.com/tech...ry/OBD_I.shtml

In the drawing of the OBD1 connector the Fuel Pump Slot is identified, if you GROUND that slot, jumper wire, then fuel pump relay will be Grounded, just like computer does, but full time.
If will be OFF with key off, but relay will close with key ON and stay closed as long as jumper is in place, it doesn't hurt anything