If fuel injectors are not working then yes it is most likely a Computer issue
Computer gets the PIP signal from TFI which the computer uses to time the injectors, actually just tells computer to wake up, engine is spinning, lol
Rangers all used the Grey colored TFI modules
Black ones were later models
SPOUT is spark advance from the computer, it serves the same purpose as Vacuum Advance did on older distributors
With fuel injection only the computer has "engine load" data, TFI just has RPM data
On the grey TFIs there is a START wire, this wire will have 12v when key is in START
This disables SPOUT connection inside the TFI module so base spark timing is used to start the engine, before spark advance is added
So you should have cranking spark regardless of SPOUT being connected or not
Article on TFI below, it has this quote
The early TFI system, which Ford calls the "Push Start" TFI system, uses a gray TFI module.
Originally, the module was mounted on the distributor. In the late '80s Ford began to relocate it away
from the distributor on some vehicles to provide better protection from the effects of engine heat, but
system operation remained the same. It uses a Hall effect pickup (stator) in the distributor, which
generates a battery voltage, 50% duty cycle square wave, called the PIP signal, to the EEC-U PCM
and the TFI module. The PCM processes this signal and sends out another battery voltage, 50% duty
cycle square wave, called the SPOUT signal, to the TFI module. As long as the TFI module is
receiving a SPOUT signal, it will fire the coil at the rising edge of that signal (except during engine
cranking, when SPOUT is ignored) and the vehicle will run with the amount of timing advance
commanded by the computer. If the TFI module does not receive the SPOUT signal, it will fire the
coil at the rising edge of the PIP signal, and the vehicle will run at base timing. This is true on all TFI
systems.
What's the spark timing when warm engine is running/idling without SPOUT connected?
Should be 10-12deg BTDC
And if you connect SPOUT, with engine still idling, spark timing should go to 20-22deg BTDC