cranks but wont start.
only a shorted starter can do that.
or alternator gone nuts but that blows the 60amp fuse seen here
you can do lots.
first and always first. check all fuse, (TEST THEM)
I had a car back in 1972 that (mech, really alternator reg)
that went nuts and blew up every lamp in car, at midnight far from home, in a bad neighborhood too.. scary, but engine ran.
your car is EFI,
and is only safe up to 15VDC< over that you blow up ECU
or if lucky (only the 3 ECU fuses blow)
is the CEL lamp working in the cluster,? if no the fuses blew.
the 3 fuses are
IG coil
FI
and dome.
there are 50 reasons for no start but based off one fact
i say fuses.
testing fuses. matters
if they look bad the are,
if they look good, they can be in fact bad,(called hairline cracks)
we test them did you? really test them,i do it live using a voltmeter
the meter NEVER EVER lies.
see? using a meter avoids going down the wrong path to H3LL.
(dog chasing tail)
now what if you measured the 3 power pins on the ECU behind
left speaker (sold my 91,4wd/2door, restored by me)
the ECU has power, (i have the schematic)
if it has power, the CEL must glow, or the ECU was burned up.
1991 are all 8valve cars, then
simple schm.
http://www.fixkick.com/ECU/8v-tbi-schematic91to95.jpg
full set.
http://www.fixkick.com/look/91-complete.pdf
starter. /charge.
http://www.fixkick.com/Charging/charge89.jpg